Edgar Filing: Eaton Vance Tax-Managed Buy-Write Income Fund

PART C

As filed with the Securities and Exchange Commission on March 29, 2017

1933 Act File No. 333-214544

1940 Act File No. 811-21676


SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM N-2

	REGISTRATION STATEMENT UNDER THE SECURITIES ACT of 1933	¨
	PRE-EFFECTIVE AMENDMENT NO. 1	x
	POST-EFFECTIVE AMENDMENT NO.	¨
	and/or
	REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940	o
	AMENDMENT NO. 5	x

EATON VANCE TAX-MANAGED BUY-WRITE INCOME FUND
(Exact Name of Registrant as Specified in Charter)

Two International Place, Boston, Massachusetts 02110
(Address of Principal Executive Offices)

(617) 482-8260
(Registrant’s Telephone Number)

Frederick S. Marius
Two International Place, Boston, Massachusetts 02110
(Name and Address of Agent for Service)

Approximate Date of Proposed Public Offering: As soon as practicable after the effective date of this Registration Statement.

If any of the securities being registered on this form are to be offered on a delayed or continuous basis in reliance on Rule 415 under the Securities Act of 1933, as amended, other than securities offered in connection with a dividend reinvestment plan, check the following box. x

It is proposed that this filing will become effective (check appropriate box):

x When declared effective pursuant to Section 8(c)

CALCULATION OF REGISTRATION FEE UNDER THE SECURITIES ACT OF 1933


Title of Securities Being Registered	Amount Being Registered⁽¹⁾	Proposed Maximum Offering Price Per Unit ⁽¹⁾	Proposed Maximum Aggregate Offering Price ⁽¹⁾	Amount of Registration Fees⁽¹⁾⁽²⁾
Common Shares $0.01 par value	2,965,949 Shares	$16.12	$47,811,098	$5,541.31

⁽¹⁾

Estimated solely for the purpose of calculating the registration fee in accordance with Rule 457(c) under the Securities Act of 1933 based on the average of the high and low sales prices of the shares of beneficial interest on March 27, 2017 as reported on the New York Stock Exchange.

⁽²⁾

A registration fee of $1.87 was previously paid in connection with the initial filing on November 10, 2016.

__________________________________________

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended or until the Registration Statement shall become effective on such dates as the Commission, acting pursuant to said Section 8(a), may determine.

ETBPROSPECTUS


PRELIMINARY PROSPECTUS	SUBJECT TO COMPLETION	April ___, 2017

The information in this prospectus is not complete and may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale would be prohibited.

(EATON VANCE LOGO)

Up to 2,965,949 Shares

Eaton Vance Tax-Managed Buy-Write Income Fund

Common Shares

Investment objectives and policies. Eaton Vance Tax-Managed Buy-Write Income Fund (the “Fund”) is a diversified, closed-end management investment company, which commenced operations on April 29, 2005. The Fund’s primary investment objective is to provide current income and gains, with a secondary objective of capital appreciation. In pursuing its investment objectives, the Fund will evaluate returns on an after-tax basis, seeking to minimize and defer shareholder federal income taxes.

Investment Adviser and Sub-Adviser. The Fund’s investment adviser is Eaton Vance Management (“Eaton Vance” or the “Adviser”). As of January 31, 2017 , Eaton Vance and its affiliates managed approximately $ 363.7 billion of fund and separate account assets on behalf of clients, including approximately $ 99.6 billion in equity assets. Eaton Vance has engaged its affiliate Parametric Portfolio Associates LLC (“Parametric” or the “Sub-Adviser”) as the sub-adviser to the Fund. Parametric managed approximately $ 185.9 billion in assets as of January 31, 2017 . Eaton Vance is responsible for managing the Fund’s overall investment program and executing the Fund’s options strategy. Eaton Vance is also responsible for providing research support to the Sub-Adviser and supervising the performance of the Sub-Adviser. Parametric is responsible for structuring and managing the Fund’s common stock portfolio, including tax-loss harvesting and other tax-management techniques, relying in part on the fundamental research and analytical judgments of the Adviser.

The Offering. The Fund may offer, from time to time, in one or more offerings (each, an “Offering”), the Fund’s common shares of beneficial interest, $0.01 par value (“Common Shares”). Common Shares may be offered at prices and on terms to be set forth in one or more supplements to this Prospectus (each, a “Prospectus Supplement”). You should read this Prospectus and the applicable Prospectus Supplement carefully before you invest in Common Shares. Common Shares may be offered directly to one or more purchasers, through agents designated from time to time by us, or to or through underwriters or dealers. The Prospectus Supplement relating to the Offering will identify any agents, underwriters or dealers involved in the offer or sale of Common Shares, and will set forth any applicable offering price, sales load, fee, commission or discount arrangement between the Fund and its agents or underwriters, or among its underwriters, or the basis upon which such amount may be calculated, net proceeds and use of proceeds, and the terms of any sale. The Fund may not sell any Common Shares through agents, underwriters or dealers without delivery of a Prospectus Supplement describing the method and terms of the particular Offering of the Common Shares. (continued on inside cover page)

The Common Shares have traded both at a premium and a discount to net asset value (“NAV”). The Fund cannot predict whether Common Shares will trade in the future at a premium or discount to NAV. The provisions of the Investment Company Act of 1940, as amended (the “1940 Act”) generally require that the public offering price of common shares (less any underwriting commissions and discounts) must equal or exceed the NAV per share of a company’s common stock (calculated within 48 hours of pricing). The Fund’s issuance of Common Shares may have an adverse effect on prices in the secondary market for the Fund’s Common Shares by increasing the number of Common Shares available, which may put downward pressure on the market price for the Fund’s Common Shares. Shares of common stock of closed-end investment companies frequently trade at a discount from NAV, which may increase investors’ risk of loss.

Investing in shares involves certain risks. See “Investment objectives, policies and risks” beginning at page 18.

Neither the Securities and Exchange Commission (“SEC”) nor any state securities commission has approved or disapproved of these securities or determined if this Prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

(continued from previous page)

Portfolio contents. Under normal market conditions, the Fund’s investment program will consist primarily of (1) owning a diversified portfolio of common stocks that seeks to exceed the total return performance of the S&P 500 Composite Stock Price Index^(R) (the “S&P 500”) and (2) selling S&P 500 call options on a continuous basis on substantially the full value of its holdings of common stocks.

The Fund will seek to generate current earnings in part by employing an options strategy of writing (selling) index call options on the S&P 500. The Fund expects to sell index call options on a continuous basis on substantially the full value of its holdings of common stocks. Under normal market conditions, at least 80% of the value of the Fund’s total assets will be subject to written index call options. Writing index call options involves a tradeoff between the option premiums received and reduced participation in potential future stock price appreciation of the Fund’s portfolio of common stocks. Generally, the Fund intends to sell S&P 500 call options that are slightly “out-of-the-money,” meaning that option exercise prices generally will be slightly higher than the current level of the index at the time the options are written. The Fund seeks to generate current earnings from option premiums and, to a lesser extent, from dividends on stocks held.

During unusual market conditions, the Fund may invest up to 100% of its assets in cash or cash equivalents temporarily, which may be inconsistent with its investment objectives, principal strategies and other policies.

Exchange listing. As of March 27, 2017 , the Fund had 24, 716,244 Common Shares outstanding. The Fund’s Common Shares are traded on the New York Stock Exchange (“NYSE”) under the symbol “ETB.” As of March 27, 2017 , the last reported sale price of a Common Share of the Fund on the NYSE was $16.14 Common Shares offered and sold pursuant to this Registration Statement will also be listed on the NYSE and trade under this symbol.

The Fund’s net asset value and distribution rate will vary and may be affected by numerous factors, including changes in stock prices, option premiums, market interest rates, dividend rates and other factors. An investment in the Fund may not be appropriate for all investors. There is no assurance that the Fund will achieve its investment objectives.

This Prospectus, together with any applicable Prospectus Supplement, sets forth concisely information you should know before investing in the shares of the Fund. Please read and retain this Prospectus for future reference. A Statement of Additional Information dated April ___, 2017 , has been filed with the SEC and can be obtained without charge by calling 1-800-262-1122 or by writing to the Fund. A table of contents to the Statement of Additional Information is located at page 42 of this Prospectus. This Prospectus incorporates by reference the entire Statement of Additional Information. The Statement of Additional Information is available along with shareholder reports and other Fund-related materials: at the SEC’s public reference room in Washington, DC (call 1-202- 551 -8090 for information on the operation of the reference room); from the EDGAR database on the SEC’s internet site (http://www.sec.gov); upon payment of copying fees by writing to the SEC’s public reference section, Washington, DC 20549- 1520 ; or by electronic mail at publicinfo@sec.gov. The Fund’s address is Two International Place, Boston, MA 02110, and its telephone number is 1-800-262-1122.

The Fund’s shares do not represent a deposit or obligation of, and are not guaranteed or endorsed by, any bank or other insured depository institution, and are not federally insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board or any other government agency.

You should rely only on the information contained or incorporated by reference in this Prospectus. The Fund has not authorized anyone to provide you with different information. The Fund is not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information contained in this Prospectus is accurate as of any date other than the date on the front of this Prospectus.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Table of Contents


Prospectus Summary	5
Summary of Fund Expenses	15
Financial Highlights and Investment Performance	16
The Fund	18
Use of Proceeds	18
Investment Objectives, Policies and Risks	18
Management of the Fund	30
Plan of Distribution	32
Distributions	33
Federal Income Tax Matters	34
Dividend Reinvestment Plan	37
Description of Capital Structure	37
Custodian and Transfer Agent	41
Legal Opinions	41
Reports to Shareholders	41
Independent Registered Public Accounting Firm	41
Additional Information	41
Table of Contents for the Statement of Additional Information	42
The Fund’s Privacy Policy	43

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

CAUTIONARY NOTICE REGARDING FORWARD-LOOKING STATEMENTS

This Prospectus, any accompanying Prospectus Supplement and the Statement of Additional Information contain “forward-looking statements.” Forward-looking statements can be identified by the words “may,” “will,” “intend,” “expect,” “estimate,” “continue,” “plan,” “anticipate,” and similar terms and the negative of such terms. Such forward-looking statements may be contained in this Prospectus as well as in any accompanying Prospectus Supplement. By their nature, all forward-looking statements involve risks and uncertainties, and actual results could differ materially from those contemplated by the forward-looking statements. Several factors that could materially affect our actual results are the performance of the portfolio of securities we hold, the price at which our shares will trade in the public markets and other factors discussed in our periodic filings with the SEC.

Although we believe that the expectations expressed in our forward-looking statements are reasonable, actual results could differ materially from those projected or assumed in our forward-looking statements. Our future financial condition and results of operations, as well as any forward-looking statements, are subject to change and are subject to inherent risks and uncertainties, such as those disclosed in the “Investment objectives, policies and risks” section of this Prospectus. All forward-looking statements contained or incorporated by reference in this Prospectus or any accompanying Prospectus Supplement are made as of the date of this Prospectus or the accompanying Prospectus Supplement, as the case may be. Except for our ongoing obligations under the federal securities laws, we do not intend, and we undertake no obligation, to update any forward-looking statement. The forward-looking statements contained in this Prospectus, any accompanying prospectus supplement and the statement of additional information are excluded from the safe harbor protection provided by section 27A of the Securities Act of 1933, as amended (the “1933 Act”).

Currently known risk factors that could cause actual results to differ materially from our expectations include, but are not limited to, the factors described in the “Investment objectives, policies and risks” section of this Prospectus. We urge you to review carefully that section for a more detailed discussion of the risks of an investment in our securities.

Prospectus dated April ___, 2017

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Prospectus Summary

The following summary is qualified in its entirety by reference to the more detailed information included elsewhere in this Prospectus, in any related Prospectus Supplement, and in the Statement of Additional Information.

THE FUND

Eaton Vance Tax-Managed Buy-Write Income Fund (the “Fund”) is a diversified, closed-end management investment company, which commenced operations on April 29, 2005. The Fund seeks to provide current income and gains, with a secondary objective of capital appreciation. Investments are based on Eaton Vance Management’s (“Eaton Vance” or the “Adviser”) and Parametric Portfolio Associates LLC’s (“Parametric” or a “Sub-Adviser”) internal research and proprietary modeling techniques and software. An investment in the Fund may not be appropriate for all investors. There is no assurance that the Fund will achieve its investment objectives.

THE OFFERING

The Fund may offer, from time to time, in one or more offerings (each, an “Offering”), up to 2,965,949 of the Fund’s common shares of beneficial interest, $0.01 par value (“Common Shares”), on terms to be determined at the time of the Offering. The Common Shares may be offered at prices and on terms to be set forth in one or more Prospectus Supplements. You should read this Prospectus and the applicable Prospectus Supplement carefully before you invest in Common Shares. Common Shares may be offered directly to one or more purchasers, through agents designated from time to time by the Fund, or to or through underwriters or dealers. The Prospectus Supplement relating to the Offering will identify any agents, underwriters or dealers involved in the offer or sale of Common Shares, and will set forth any applicable offering price, sales load, fee, commission or discount arrangement between the Fund and its agents or underwriters, or among its underwriters, or the basis upon which such amount may be calculated, net proceeds and use of proceeds, and the terms of any sale. See “Plan of Distribution.” The Fund may not sell any of Common Shares through agents, underwriters or dealers without delivery of a Prospectus Supplement describing the method and terms of the particular Offering of Common Shares.

INVESTMENT OBJECTIVES AND POLICIES

Under normal market conditions, the Fund’s investment program will consist primarily of (1) owning a diversified portfolio of common stocks that seeks to exceed the total return performance of the S&P 500 Composite Stock Price Index ® (the “S&P 500”) and (2) selling S&P 500 call options on a continuous basis on substantially the full value of its holdings of common stocks.

Under normal market conditions, the Fund will invest at least 80% of its total assets in a diversified portfolio of common stocks that seeks to exceed the total return performance of the S&P 500. Due to tax considerations, the Fund intends to limit the overlap between its stock portfolio holdings (and any subset thereof) and the S&P 500 to less than 70% on an ongoing basis. The Fund will invest primarily in common stocks of U.S. issuers. The Fund may invest up to 10% of its total assets in securities of foreign issuers, including American Depositary Receipts (“ADRs”), Global Depositary Receipts (“GDRs”) and European Depositary Receipts (“EDRs”). The Fund normally expects that its assets will be invested across a broad range of industries and market sectors. The Fund may not invest 25% or more of its total assets in the securities of issuers in any single industry or group of industries. The Fund may invest a portion of its assets in stocks of mid-capitalization companies. Eaton Vance generally considers mid-capitalization companies to be those companies having market capitalizations within the range of capitalizations for the S&P MidCap 400 Index (“S&P MidCap 400”). As of February 28, 2017 , the median market capitalization of companies in the S&P MidCap 400 was approximately $3. 9 billion.

The Fund will seek to generate current earnings in part by employing an options strategy of writing (selling) index call options on the S&P 500. The Fund expects to sell index call options on a continuous basis on substantially the full value of its holdings of common stocks. Under normal market conditions, at least 80% of the value of the Fund’s total assets will be subject to written index call options. Writing index call options involves a tradeoff between the option premiums received and reduced participation in potential future stock price appreciation of the Fund’s portfolio of common stocks. The Fund seeks to generate current earnings from option premiums and, to a lesser extent, from dividends on stocks held.

The Fund intends to sell S&P 500 call options that are exchange-listed and “European style,” meaning that the options may be exercised only on the expiration date of the option. Index options differ from options on individual securities in that index options (i) typically are settled in cash rather than by delivery of securities and (ii) reflect price fluctuations in a group of securities or segments of the securities market rather than price fluctuations in a single security.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

As the seller of S&P 500 call options, the Fund will receive cash (the premiums) from option purchasers. The purchaser of an S&P 500 call option has the right to any appreciation in the value of the S&P 500 over a fixed price (the exercise price) as of a specified date in the future (the option valuation date). Generally, the Fund intends to sell S&P 500 call options that are slightly “out-of-the-money” (i.e., the exercise price generally will be slightly above the current level of the S&P 500 when the option is sold). The Fund will, in effect, sell the potential appreciation in the value of the S&P 500 above the exercise price in exchange for the option premium received. If, at expiration, an S&P 500 call option sold by the Fund is exercised, the Fund will pay the purchaser the difference between the cash value of the S&P 500 and the exercise price of the option. The premium, the exercise price and the market value of the S&P 500 will determine the gain or loss realized by the Fund as the seller of the index call option.

The Fund’s policies, under normal market conditions, that the Fund will invest at least 80% of its total assets in a diversified portfolio of common stocks that seeks to exceed the total return performance of the S&P 500 and that at least 80% of the value of the Fund’s total assets will be subject to written index call options on a continuous basis are non-fundamental policies and may be changed by the Fund’s Board of Trustees (the “Board”) without Common Shareholder approval following the provision of 60 days prior written notice to Common Shareholders.

In implementing the Fund’s investment strategy, the Adviser and Sub-Adviser intend to employ a variety of techniques and strategies designed to minimize and defer the federal income taxes incurred by shareholders in connection with their investment in the Fund as described below.

The S&P 500 is an unmanaged index of 500 stocks maintained and published by Standard & Poor’s that is market-capitalization weighted and generally representative of the performance of larger stocks traded in the United States. It is not possible to invest directly in an index. The Fund is not sponsored, endorsed, sold or promoted by Standard & Poor’s. Standard & Poor’s has not passed on the legality or suitability of, or the accuracy or adequacy of descriptions and disclosures relating to the Fund. Standard & Poor’s makes no representation regarding the advisability of investing in the Fund.

INVESTMENT SELECTION STRATEGIES

Eaton Vance is responsible for managing the Fund’s overall investment program and executing the Fund’s options strategy. Eaton Vance also is responsible for providing research support to the Sub-Adviser and supervising the performance of the Sub-Adviser. Parametric will be responsible for structuring and managing the Fund’s common stock portfolio, including tax-loss harvesting and other tax-management techniques, relying in part on the fundamental research and analytical judgments of the Adviser. The Fund’s investments are actively managed, and securities may be bought or sold on a daily basis.

The Fund’s strategy consists of owning a portfolio of common stocks and selling covered call options (a “buy-write strategy”).

To avoid being subject to the “straddle rules” under federal income tax law, the Fund intends to maintain an overlap of less than 70% between its stock portfolio (or any subset thereof) and the S&P 500 on an ongoing basis. Under the “straddle rules,” “offsetting positions with respect to personal property” generally are considered to be straddles. In general, investment positions will be offsetting if there is a substantial diminution in the risk of loss from holding one position by reason of holding one or more other positions. The Fund expects that the index call options it writes will not be considered straddles because the Fund’s portfolio of common stocks will be sufficiently dissimilar from the components of the S&P 500 under applicable guidance established by the Internal Revenue Service (“IRS”). Under certain circumstances, however, the Fund may enter into options transactions or certain other investments that may constitute positions in a straddle. Parametric will consider a variety of factors in constructing and maintaining the Fund’s stock portfolio, including, but not limited to, stock performance ratings as determined by the Adviser, stock dividend yields, overlap between the stock portfolio holdings and the S&P 500, projected tracking of the stock portfolio versus the S&P 500, realization of loss harvesting opportunities and other tax management considerations. The Adviser’s evaluation of the future performance potential of individual stocks will be one among several considerations in portfolio construction and will not, on a standalone basis, be determinative of portfolio construction. The Adviser’s stock ratings will be based primarily on fundamental research.

The Fund’s index option strategy is designed to produce current cash flow from options premiums and to moderate the volatility of the Fund’s returns. This index option strategy is of a hedging nature and is not designed to speculate on equity market performance. The Adviser believes that the Fund’s index option strategy will moderate the volatility of the Fund’s returns because the option premiums received will help to mitigate the impact of downward price movements in the stocks held by the Fund, while the Fund’s obligations under index calls written will effectively limit the Fund’s ability to participate in upward price movements in portfolio stocks beyond certain levels.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

The Fund expects to sell index call options on a continuous basis on substantially the full value of its holdings of common stocks. Under normal conditions, at least 80% of the value of the Fund’s total assets will be subject to written index call options. The Adviser does not intend to sell index call options representing amounts greater than the value of the Fund’s common stock portfolio (i.e., take a “naked” position). The Adviser intends to sell S&P 500 call options that are exchange-listed and “European style,” meaning that the options may only be exercised on the expiration date of the option. Exchange-traded index options are typically settled in cash and provide that the holder of the option has the right to receive an amount of cash determined by the excess of the exercise-settlement value of the index over the exercise price of the option. The exercise-settlement value is calculated based on opening sales prices of the component index stocks on the option valuation date, which is the last business day before the expiration date. Generally, the Adviser intends to sell S&P 500 call options that are slightly “out-of-the-money,” meaning that option exercise prices generally will be slightly above the current level of the index at the time the options are written. Options on broad-based equity indices that trade on a national securities exchange registered with the Securities and Exchange Commission (“SEC”) or a domestic board of trade designated as a contract market by the Commodity Futures Trading Commission generally qualify for treatment as “section 1256 contracts” as defined in the Internal Revenue Code of 1986, as amended (the “Code”). Under the Code, capital gains and losses on “section 1256 contracts” are generally recognized annually based on a marking-to-market of open positions at tax year-end, with gains or losses treated as 60% long-term and 40% short-term, regardless of holding period.

In implementing the Fund’s investment strategy, the Adviser and the Sub-Adviser intend to employ a variety of techniques and strategies designed to minimize and defer the federal income taxes incurred by Common Shareholders in connection with their investment in the Fund. These include: (1) selling index call options that qualify for treatment as “section 1256 contracts” on which capital gains and losses are generally treated as 60% long-term and 40% short-term, regardless of holding period; (2) limiting the overlap of the Fund’s stock portfolio (and any subset thereof) versus the S&P 500 to less than 70% so that the Fund’s stock holdings and S&P 500 call options are not subject to the “straddle rules;” (3) engaging in a systematic program of tax-loss harvesting in the Fund’s stock portfolio, periodically selling stock positions that have depreciated in value to realize capital losses that can be used to offset capital gains realized by the Fund; and (4) managing the sale of appreciated stock positions so as to minimize the Fund’s net realized short-term capital gains in excess of net realized long-term capital losses. When an appreciated security is sold, the Fund generally seeks to select for sale the share lots resulting in the most favorable tax treatment, normally those with holding periods sufficient to qualify for long-term capital gains treatment that have the highest cost basis.

In addition, the Fund will seek to earn and distribute “qualified dividend income.” Qualified dividend income received by an individual is taxed at the rates applicable to long-term capital gain (currently at a maximum rate of 20% plus a 3.8% Medicare contribution tax). In order for a dividend received by Fund shareholders to be qualified dividend income, the Fund must meet holding period and other requirements with respect to the dividend-paying stock in its portfolio and the shareholder must meet holding period and other requirements with respect to the Fund’s shares. A dividend will not be treated as qualified dividend income (at either the Fund or shareholder level) (1) if the dividend is received with respect to any share of stock held for fewer than 61 days during the 121-day period beginning at the date which is 60 days before the date on which such share becomes ex-dividend with respect to such dividend (or, in the case of certain preferred stock, 91 days during the 181-day period beginning 90 days before such date), (2) to the extent that the recipient is under an obligation (whether pursuant to a short sale or otherwise) to make related payments with respect to positions in substantially similar or related property, (3) if the recipient elects to have the dividend income treated as investment interest, or (4) if the dividend is received from a foreign corporation that is (a) not eligible for the benefits of a comprehensive income tax treaty with the U.S. (with the exception of dividends paid on stock of such a foreign corporation readily tradable on an established securities market in the U.S.) or (b) treated as a passive foreign investment company. Payments in lieu of dividends, such as payments pursuant to securities lending arrangements, also do not qualify to be treated as qualified dividend income. In general, distributions of investment income reported by the Fund as derived from qualified dividend income will be treated as qualified dividend income by a shareholder taxed as an individual provided the shareholder meets the holding period and other requirements described above with respect to the Fund’s shares.

The Fund may seek to enhance the level of tax-advantaged dividend income it receives by emphasizing higher-yielding stocks in its stock portfolio and by engaging in dividend capture trading. In a dividend capture trade, the Fund sells a stock on or shortly after the stock’s ex-dividend date and uses the sale proceeds to purchase one or more other stocks that are expected to pay dividends before the next dividend payment on the stock being sold. Through this practice, the Fund may receive more dividend payments over a given time period than if it held a single stock. In order for dividends received by the Fund to qualify for favorable tax treatment, the Fund must comply with the holding period and other requirements set forth in the preceding paragraph. By complying with the applicable holding period and other requirements while engaging in dividend capture trading, the Fund may be able to enhance the level of tax-advantaged dividend income it receives because it will receive more dividend payments qualifying for favorable treatment during the same time period than if it simply held its portfolio stocks. The use of dividend capture trading strategies will expose the Fund to increased trading costs and potentially higher short-term gain or loss.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

The foregoing policies relating to investment in common stocks and options writing are the Fund’s primary investment policies. In addition to its primary investment policies, the Fund may invest to a limited extent in other types of securities and engage in certain other investment practices. In addition to writing index call options, the Fund may invest up to 20% of its total assets in derivative instruments acquired for hedging, risk management and investment purposes (to gain exposure to securities, securities markets, markets indices and/or currencies consistent with its investment objectives and policies), provided that no more than 10% of the Fund’s total assets may be invested in such derivative instruments acquired for non-hedging purposes. To seek to protect against price declines in securities holdings with large accumulated gains, the Fund may use various hedging techniques (such as the purchase and sale of futures contracts on stocks and stock indices and options thereon, equity swaps, covered short sales, forward sales of stocks and the purchase and sale of forward currency exchange contracts and currency futures). By using these techniques rather than selling appreciated securities, the Fund can, within certain limitations, reduce its exposure to price declines in the securities without realizing substantial capital gains under current tax law. Derivative instruments may also be used by the Fund to enhance returns or as a substitute for the purchase or sale of securities. As a general matter, dividends received on hedged stock positions are characterized as ordinary income and are not eligible for favorable tax treatment. Dividends received on securities with respect to which the Fund is obligated to make related payments (pursuant to short sales or otherwise) will be treated as fully taxable ordinary income (i.e., income other than tax-advantaged dividends). In addition, use of derivatives may give rise to short-term capital gains and other income that would not qualify for favorable tax treatment. See “Investment Objectives, Policies and Risks.”

LISTING

As of March 27, 2017 , The Fund had 24, 716,244 Common Shares outstanding. The Fund’s Common Shares are traded on the New York Stock Exchange (“NYSE”) under the symbol “ETB.” As of March 27, 2017 , the last reported sale price of a Common Share of the Fund on the NYSE was $16.14 Common Shares offered and sold pursuant to this Registration Statement will also be listed on the NYSE and trade under this symbol.

INVESTMENT ADVISER, ADMINISTRATOR AND SUB-ADVISER

Eaton Vance, a wholly-owned subsidiary of Eaton Vance Corp., is the Fund’s investment adviser and administrator. As of January 31, 2017 , Eaton Vance and its affiliates managed approximately $ 363.7 billion of fund and separate account assets on behalf of clients, including approximately $ 99.6 billion in equity assets. Eaton Vance has engaged Parametric, an indirect, majority-owned subsidiary of Eaton Vance Corp., as a sub-adviser to the Fund. Parametric managed approximately $ 185.9 billion in assets as of January 31, 2017 .. Eaton Vance is responsible for managing the Fund’s overall investment program and executing the Fund’s options strategy. Eaton Vance also is responsible for providing research support to the Sub-Adviser and supervising the performance of the Sub-Adviser. Parametric is responsible for structuring and managing the Fund’s common stock portfolio, including tax-loss harvesting and other tax-management techniques, relying in part on the fundamental research and analytical judgments of the Adviser. See “Management of the Fund.”

PLAN OF DISTRIBUTION

The Fund may sell the Common Shares being offered under this Prospectus in any one or more of the following ways: (i) directly to purchasers; (ii) through agents; (iii) to or through underwriters; or (iv) through dealers. The Prospectus Supplement relating to the Offering will identify any agents, underwriters or dealers involved in the offer or sale of Common Shares, and will set forth any applicable offering price, sales load, fee, commission or discount arrangement between the Fund and its agents or underwriters, or among its underwriters, or the basis upon which such amount may be calculated, net proceeds and use of proceeds, and the terms of any sale.

The Fund may distribute Common Shares from time to time in one or more transactions at: (i) a fixed price or prices that may be changed; (ii) market prices prevailing at the time of sale; (iii) prices related to prevailing market prices; or (iv) negotiated prices; provided, however, that in each case the offering price per Common Share (less any underwriting commission or discount) must equal or exceed the NAV per Common Share.

The Fund from time to time may offer its Common Shares through or to certain broker-dealers, including UBS Securities LLC, that have entered into selected dealer agreements relating to at-the-market offerings.

The Fund may directly solicit offers to purchase Common Shares, or the Fund may designate agents to solicit such offers. The Fund will, in a Prospectus Supplement relating to such Offering, name any agent that could be viewed as an underwriter under the 1933 Act, and describe any commissions the Fund must pay to such agent(s). Any such agent will be acting on a reasonable best efforts basis for the period of its appointment or, if indicated in the applicable Prospectus Supplement or other offering materials, on a firm commitment basis. Agents, dealers and underwriters may be customers of, engage in transactions with, or perform services for the Fund in the ordinary course of business.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

If any underwriters or agents are used in the sale of Common Shares in respect of which this Prospectus is delivered, the Fund will enter into an underwriting agreement or other agreement with them at the time of sale to them, and the Fund will set forth in the Prospectus Supplement relating to such Offering their names and the terms of the Fund’s agreement with them.

If a dealer is utilized in the sale of Common Shares in respect of which this Prospectus is delivered, the Fund will sell such Common Shares to the dealer, as principal. The dealer may then resell such Common Shares to the public at varying prices to be determined by such dealer at the time of resale.

The Fund may engage in at-the-market offerings to or through a market maker or into an existing trading market, on an exchange or otherwise, in accordance with Rule 415(a)(4) under the 1933 Act. An at-the-market offering may be through an underwriter or underwriters acting as principal or agent for the Fund.

Agents, underwriters and dealers may be entitled under agreements which they may enter into with the Fund to indemnification by the Fund against certain civil liabilities, including liabilities under the 1933 Act, and may be customers of, engage in transactions with or perform services for the Fund in the ordinary course of business.

In order to facilitate the Offering of Common Shares, any underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of Common Shares or any other Common Shares the prices of which may be used to determine payments on the Common Shares. Specifically, any underwriters may over-allot in connection with the Offering, creating a short position for their own accounts. In addition, to cover over-allotments or to stabilize the price of Common Shares or of any such other Common Shares, the underwriters may bid for, and purchase, Common Shares or any such other Common Shares in the open market. Finally, in any Offering of Common Shares through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing Common Shares in the Offering if the syndicate repurchases previously distributed Common Shares in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of Common Shares above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.

The Fund may enter into derivative transactions with third parties, or sell Common Shares not covered by this Prospectus to third parties in privately negotiated transactions. If the applicable Prospectus Supplement indicates, in connection with those derivatives, the third parties may sell Common Shares covered by this Prospectus and the applicable Prospectus Supplement or other offering materials, including in short sale transactions. If so, the third parties may use Common Shares pledged by the Fund or borrowed from the Fund or others to settle those sales or to close out any related open borrowings of securities, and may use Common Shares received from the Fund in settlement of those derivatives to close out any related open borrowings of securities. The third parties in such sale transactions will be underwriters and, if not identified in this Prospectus, will be identified in the applicable Prospectus Supplement or other offering materials (or a post-effective amendment).

The maximum amount of compensation to be received by any member of the Financial Industry Regulatory Authority, Inc. will not exceed 8% of the initial gross proceeds from the sale of any security being sold with respect to each particular Offering of Common Shares made under a single Prospectus Supplement.

Any underwriter, agent or dealer utilized in the initial Offering of Common Shares will not confirm sales to accounts over which it exercises discretionary authority without the prior specific written approval of its customer.

DISTRIBUTIONS

Pursuant to an exemptive order issued by the Securities and Exchange Commission (“Order”), the Fund is authorized to distribute long-term capital gains to shareholders more frequently than once per year. Pursuant to the Order, the Fund’s Board of Trustees approved a Managed Distribution Plan (“MDP”) pursuant to which the Fund makes monthly cash distributions to Common Shareholders, stated in terms of a fixed amount per common share. Shareholders should not draw any conclusions about the Fund’s investment performance from the amount of these distributions or from the terms of the MDP. The MDP will be subject to regular periodic review by the Fund’s Board of Trustees and the Board may amend or terminate the MDP at any time without prior notice to Fund shareholders. However, at this time there are no reasonably foreseeable circumstances that might cause the termination of the MDP. The Fund may distribute more than its net investment income and net realized capital gains and, therefore, a distribution may include a return of capital. A return of capital distribution does not necessarily reflect the Fund’s investment performance and should not be confused with “yield” or “income.” With each distribution, the Fund will issue a notice to shareholders and a press release containing information about the amount and sources of the distribution and other related information. The amounts and sources of distributions contained in the notice and press release are only estimates and are not provided for tax purposes. The amounts and sources of the Fund’s distributions for tax purposes will be reported to shareholders on Form 1099-DIV for each calendar year.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Subject to its MDP, the Fund makes monthly distributions to Common Shareholders sourced from the Fund’s cash available for distribution. “Cash available for distribution” consists of the Fund’s dividends and interest income after payment of Fund expenses, net option premiums and net realized and unrealized gains on stock investments. The Fund intends to distribute all or substantially all of its net realized capital gains. Distributions are recorded on the ex-dividend date. Distributions to shareholders are determined in accordance with income tax regulations, which may differ from U.S. GAAP. As required by U.S. GAAP, only distributions in excess of tax basis earnings and profits are reported in the financial statements as a return of capital. Permanent differences between book and tax accounting relating to distributions are reclassified to paid-in capital. For tax purposes, distributions from short-term capital gains are considered to be from ordinary income. Distributions in any year may include a substantial return of capital component. The Fund’s distribution rate may be adjusted from time-to-time. The Board may modify this distribution policy at any time without obtaining the approval of Common Shareholders.

Common Shareholders may elect automatically to reinvest some or all of their distributions in additional Common Shares under the Fund’s dividend reinvestment plan. See “Distributions” and “Dividend Reinvestment Plan.”

DIVIDEND REINVESTMENT PLAN

The Fund has established a dividend reinvestment plan (the “Plan”). Under the Plan, a Common Shareholder may elect to have all dividend and capital gain distributions automatically reinvested in additional Common Shares either purchased in the open market or newly issued by the Fund if the Common Shares are trading at or above their net asset value. Common Shareholders may elect to participate in the Plan by completing the dividend reinvestment plan application form. Common Shareholders who do not elect to participate in the Plan will receive all distributions in cash paid by check mailed directly to them by American Stock Transfer & Trust Company, LLC, as dividend paying agent. Common Shareholders who intend to hold their Common Shares through a broker or nominee should contact such broker or nominee to determine whether or how they may participate in the Plan. See “Dividend Reinvestment Plan.”

CLOSED-END STRUCTURE

Closed-end funds differ from open-end management investment companies (commonly referred to as mutual funds) in that closed-end funds generally list their shares for trading on a securities exchange and do not redeem their shares at the option of the shareholder. By comparison, mutual funds issue securities that are redeemable at net asset value at the option of the shareholder and typically engage in a continuous offering of their shares. Mutual funds are subject to continuous asset in-flows and out-flows that can complicate portfolio management, whereas closed-end funds generally can stay more fully invested in securities consistent with the closed-end fund’s investment objectives and policies. In addition, in comparison to open-end funds, closed-end funds have greater flexibility in the employment of financial leverage and in the ability to make certain types of investments, including investments in illiquid securities.

However, common shares of closed-end funds frequently trade at a discount from their net asset value. Since inception, the market price of the Common Shares has fluctuated and at times traded below the Fund’s NAV, and at times has traded above NAV. In recognition of this possibility that the Common Shares might trade at a discount to net asset value and that any such discount may not be in the interest of Common Shareholders, the Fund’s Board, in consultation with Eaton Vance, from time to time may review possible actions to reduce any such discount. The Board might consider open market repurchases or tender offers for Common Shares at net asset value. There can be no assurance that the Board will decide to undertake any of these actions or that, if undertaken, such actions would result in the Common Shares trading at a price equal to or close to net asset value per Common Share. The Board might also consider the conversion of the Fund to an open-end mutual fund. The Board believes, however, that the closed-end structure is desirable, given the Fund’s investment objectives and policies. Investors should assume, therefore, that it is highly unlikely that the Board would vote to convert the Fund to an open-end investment company.

SPECIAL RISK CONSIDERATIONS

Risk is inherent in all investing. Investing in any investment company security involves risk, including the risk that you may receive little or no return on your investment or you may lose part or all of your investment.

Discount from or premium to NAV

The Offering will be conducted only when Common Shares of the Fund are trading at a price equal to or above the Fund’s NAV per Common Share plus the per Common Share amount of commissions. As with any security, the market value of the Common Shares may increase or decrease from the amount initially paid for the Common Shares. The Fund’s Common Shares have traded both at a premium and at a discount relative to NAV. The shares of closed-end management investment companies frequently trade at a discount from their NAV. This is a risk separate and distinct from the risk that the Fund’s NAV may decrease.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Secondary market for the Common Shares

The issuance of Common Shares through the Offering may have an adverse effect on the secondary market for the Common Shares. The increase in the amount of the Fund’s outstanding Common Shares resulting from the Offering may put downward pressure on the market price for the Common Shares of the Fund. Common Shares will not be issued pursuant to the Offering at any time when Common Shares are trading at a price lower than a price equal to the Fund’s NAV per Common Share plus the per Common Share amount of commissions.

The Fund also issues Common Shares of the Fund through its dividend reinvestment plan. See “Dividend Reinvestment Plan.” Common Shares may be issued under the plan at a discount to the market price for such Common Shares, which may put downward pressure on the market price for Common Shares of the Fund.

When the Common Shares are trading at a premium, the Fund may also issue Common Shares of the Fund that are sold through transactions effected on the NYSE. The increase in the amount of the Fund’s outstanding Common Shares resulting from that offering may also put downward pressure on the market price for the Common Shares of the Fund.

The voting power of current shareholders will be diluted to the extent that such shareholders do not purchase shares in any future Common Share offerings or do not purchase sufficient shares to maintain their percentage interest. In addition, if the Adviser is unable to invest the proceeds of such offering as intended, the Fund’s per share distribution may decrease (or may consist of return of capital) and the Fund may not participate in market advances to the same extent as if such proceeds were fully invested as planned.

Investment and market risk

An investment in Common Shares is subject to investment risk, including the possible loss of the entire principal amount invested. An investment in Common Shares represents an indirect investment in the securities owned by the Fund, which are generally traded on a securities exchange or in the over-the-counter markets. The value of these securities, like other market investments, may move up or down, sometimes rapidly and unpredictably. Because the Fund intends to sell index call options on a continuous basis on substantially the full value of its common stock holdings, the Fund’s appreciation potential from equity market performance will be limited. The Common Shares at any point in time may be worth less than the original investment, even after taking into account any reinvestment of distributions.

Issuer risk

The value of securities held by the Fund may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods and services.

Equity risk

Under normal market conditions, the Fund will invest its managed assets in a diversified portfolio of common stocks. Therefore, a principal risk of investing in the Fund is equity risk. The value of equity investments and related instruments may decline in response to adverse changes in the economy or the economic outlook; deterioration in investor sentiment; interest rate, currency, and commodity price fluctuations; adverse geopolitical, social or environmental developments; issuer- and sector-specific considerations; and other factors. Market conditions may affect certain types of stocks to a greater extent than other types of stocks. If the stock market declines, the value of Fund shares will also likely decline. Although stock prices can rebound, there is no assurance that values will return to previous levels. Preferred stocks and other hybrid securities may also be sensitive to changes in interest rates; when interest rates rise, their value will generally fall.

Risks of investing in mid-cap companies

The Fund may make investments in stocks of companies whose market capitalization is considered middle sized or “mid-cap.” Mid-cap companies often are newer or less established companies than larger companies. Investments in mid-cap companies carry additional risks because earnings of these companies tend to be less predictable; they often have limited product lines, markets, distribution channels or financial resources; and the management of such companies may be dependent upon one or a few key people. The market movements of equity securities of mid-cap companies may be more abrupt or erratic than the market movements of equity securities of larger, more established companies or the stock market in general. Historically, mid-cap companies have sometimes gone through extended periods when they did not perform as well as larger companies. In addition, equity securities of mid-cap companies generally are less liquid than those of larger companies. This means that the Fund could have greater difficulty selling such securities at the time and price that the Fund would like.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Risk of selling index call options

The Fund expects to sell S&P 500 call options on a continuous basis on substantially the full value of its holdings of common stocks. The purchaser of an index call option has the right to any appreciation in the value of the index over the exercise price of the call option as of the valuation date of the option. Because their exercise is settled in cash, sellers of index call options such as the Fund cannot provide in advance for their potential settlement obligations by acquiring and holding the underlying securities. The Fund intends to mitigate the risks of its written index call positions by holding a diversified portfolio of stocks similar to those on which the S&P 500 is based. However, the Fund does not intend to acquire and hold a portfolio containing exactly the same stocks as the S&P 500. Due to tax considerations, the Fund intends to limit the overlap between its stock portfolio holdings (and any subset thereof) and the S&P 500 to less than 70% on an ongoing basis. Consequently, the Fund bears the risk that the performance of the securities held will vary from the performance of the S&P 500. Index options written by the Fund will be priced on a daily basis. Their value will be affected primarily by changes in the price and dividend rates of the underlying common stocks in the S&P 500, changes in actual or perceived volatility of the S&P 500 and the remaining time to the options’ expiration. The trading price of S&P 500 call options will also be affected by liquidity considerations and the balance of purchase and sale orders.

A decision as to whether, when and how to use options involves the exercise of skill and judgment, and even a well-conceived and well-executed options program may be adversely affected by market behavior or unexpected events. As the writer of S&P 500 call options, the Fund will forgo, during the option’s life, the opportunity to profit from increases in the value of the S&P 500 above the sum of the option premium received and the exercise price of the call option, but retains the risk of loss, minus the option premium received, should the value of the S&P 500 decline. When a call option is exercised, the Fund will be required to deliver an amount of cash determined by the excess of the value of S&P 500 at contract termination over the exercise price of the option. Thus, the exercise of index call options sold by the Fund may require the Fund to sell portfolio securities to generate cash at inopportune times or for unattractive prices.

The trading price of options may be adversely affected if the market for such options becomes less liquid or smaller. The Fund may close out a call option by buying the option instead of letting it expire or be exercised. There can be no assurance that a liquid market will exist when the Fund seeks to close out a call option position by buying the option. Reasons for the absence of a liquid secondary market on an exchange include the following: (i) there may be insufficient trading interest in certain options; (ii) restrictions may be imposed by an exchange on opening transactions or closing transactions or both; (iii) trading halts, suspensions or other restrictions may be imposed with respect to particular classes or series of options; (iv) unusual or unforeseen circumstances may interrupt normal operations on an exchange; (v) the facilities of an exchange or the Options Clearing Corporation (the “OCC”) may not at all times be adequate to handle current trading volume; or (vi) one or more exchanges could, for economic or other reasons, decide or be compelled to discontinue the trading of options (or a particular class or series of options) at some future date. If trading were discontinued, the secondary market on that exchange (or in that class or series of options) would cease to exist. However, outstanding options on that exchange that had been issued by the OCC as a result of trades on that exchange would continue to be exercisable in accordance with their terms.

The hours of trading for options may not conform to the hours during which common stocks held by the Fund are traded. To the extent that the options markets close before the markets for securities, significant price and rate movements can take place in the securities markets that would not be reflected concurrently in the options markets. Index call options are marked to market daily and their value is affected by changes in the value and dividend rates of the securities represented in the underlying index, changes in interest rates, changes in the actual or perceived volatility of the associated index and the remaining time to the options’ expiration, as well as trading conditions in the options market.

Tax risk

Reference is made to “Federal Income Tax Matters” for an explanation of the federal income tax consequences and attendant risks of investing in the Fund. Although the Fund seeks to minimize and defer the federal income taxes incurred by Common Shareholders in connection with their investment in the Fund, there can be no assurance that it will be successful in this regard. Market conditions may limit the Fund’s ability to generate tax losses or to generate dividend income taxed at favorable tax rates. The Fund’s tax-managed strategy may cause the Fund to hold a security in order to achieve more favorable tax-treatment or to sell a security in order to create tax losses. The Fund’s ability to utilize various tax-management techniques may be curtailed or eliminated in the future by tax legislation or regulation. Distributions paid on the Common Shares may be characterized variously as net investment income (taxable at ordinary income rates), qualified dividends and capital gains dividends (each taxable at long-term capital gains rates) or return of capital (not currently taxable). The ultimate tax characterization of the Fund’s distributions made in a calendar year may not finally be determined until after the end of that calendar year. Distributions to a Common Shareholder that are return of capital will be tax free to the amount of the Common Shareholder’s current tax basis in his or her Common Shares, with any distribution amounts exceeding such basis treated as capital gain on a deemed sale of Common Shares. Common Shareholders are required to reduce their tax basis in Common Shares by the amount of tax-free

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

return of capital distributions received, thereby increasing the amount of capital gain (or decreasing the amount of capital loss) to be recognized upon a later disposition of the Common Shares. In order for Fund distributions of qualified dividend income to be taxable at favorable long-term capital gains rates, a Common Shareholder must meet certain prescribed holding period and other requirements with respect to his or her Common Shares. If positions held by the Fund were treated as “straddles” for federal income tax purposes, dividends on such positions would not constitute qualified dividend income subject to favorable income tax treatment. Gain or loss on positions in a straddle are subject to special (and generally disadvantageous) rules as described under “Federal Income Tax Matters.”

Foreign securities risk

As an alternative to holding foreign-traded securities, the Fund may invest in dollar-denominated securities of foreign companies that trade on U.S. exchanges or in the U.S. over-the-counter market (including depositary receipts, which evidence ownership in underlying foreign securities). Since the Fund may invest in securities denominated or quoted in currencies other than the U.S. dollar, the Fund may be affected by changes in foreign currency exchange rates (and exchange control regulations) which affect the value of investments held by the Fund and the accrued income and appreciation or depreciation of the investments in U.S. dollars. Changes in foreign currency exchange rates relative to the U.S. dollar will affect the U.S. dollar value of the Fund’s assets denominated in that currency and the Fund’s return on such assets as well as any temporary uninvested reserves in bank deposits in foreign currencies. In addition, the Fund will incur costs in connection with conversions between various currencies.

Interest rate risk

The premiums from writing index call options and amounts available for distribution from the Fund’s options activity may decrease in declining interest rate environments. The value of the Fund’s common stock investments may also be influenced by changes in interest rates. Higher yielding stocks and stocks of issuers whose businesses are substantially affected by changes in interest rates may be particularly sensitive to interest rate risk.

Dividend capture trading risk

The use of dividend capture strategies will expose the Fund to higher portfolio turnover, increased trading costs and potential for capital loss or gain, particularly in the event of significant short-term price movements of stocks subject to dividend capture trading.

Derivatives risk

In addition to writing index call options, the risks of which are described above, the Fund may invest up to 20% of its total assets in other derivative investments acquired for hedging, risk management and investment purposes, provided that no more than 10% of the Fund’s total assets may be invested in such derivative instruments acquired for non-hedging purposes. The use of derivatives can lead to losses because of adverse movements in the price or value of the asset, index, rate or instrument underlying a derivative, due to failure of a counterparty or due to tax or regulatory constraints. Derivatives may create investment leverage in the Fund, which magnifies the Fund’s exposure to the underlying investment. Derivative risks may be more significant when they are used to enhance return or as a substitute for a position or security, rather than solely to hedge the risk of a position or security held by the Fund. Derivatives for hedging purposes may not reduce risk if they are not sufficiently correlated to the position being hedged. A decision as to whether, when and how to use derivatives involves the exercise of specialized skill and judgment, and even a well-conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events. Changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index, and the Fund could lose more than the principal amount invested in derivatives. Derivative instruments traded in over-the-counter markets may be difficult to value, may be illiquid, and may be subject to wide swings in valuation caused by changes in the value of the underlying instrument. The loss on derivative transactions may substantially exceed the initial investment.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Liquidity risk

The Fund may invest up to 15% of its total assets in securities for which there is no readily available trading market or which are otherwise illiquid. The Fund may not be able readily to dispose of such securities at prices that approximate those at which the Fund could sell such securities if they were more widely traded and, as a result of such illiquidity, the Fund may have to sell other investments or engage in borrowing transactions if necessary to raise cash to meet its obligations. In addition, the limited liquidity could affect the market price of the securities, thereby adversely affecting the Fund’s net asset value, and at times may make the disposition of securities impracticable.

Inflation risk

Inflation risk is the risk that the value of assets or income from investments will be worth less in the future as inflation decreases the value of money. As inflation increases, the real value of the Common Shares and distributions thereon can decline.

Market discount risk

As with any security, the market value of the Common Shares may increase or decrease from the amount initially paid for the Common Shares. The Fund’s Common Shares have traded both at a premium and at a discount relative to NAV. The shares of closed-end management investment companies frequently trade at a discount from their NAV. This is a risk separate and distinct from the risk that the Fund’s NAV may decrease.

Financial leverage risk

Although the Fund has no current intention to do so, the Fund is authorized and reserves the flexibility to utilize leverage through the issuance of preferred shares and/or borrowings, including the issuance of debt securities. In the event that the Fund determines in the future to utilize investment leverage, there can be no assurance that such a leveraging strategy will be successful during any period in which it is employed. Leverage creates risks for Common Shareholders, including the likelihood of greater volatility of net asset value and market price of the Common Shares and the risk that fluctuations in distribution rates on any preferred shares and costs of borrowings may affect the return to Common Shareholders. To the extent the income derived from investments purchased with funds received from leverage exceeds the cost of leverage, the Fund’s distributions may be greater than if leverage had not been used. Conversely, if the income from the investments purchased with such funds is not sufficient to cover the cost of leverage, the amount available for distribution to Common Shareholders will be less than if leverage had not been used. In the latter case, Eaton Vance, in its best judgment, may nevertheless determine to maintain the Fund’s leveraged position if it deems such action to be appropriate. The costs of an offering of preferred shares and/or a borrowing program would be borne by Common Shareholders and consequently would result in a reduction of the net asset value of Common Shares. In addition, as discussed under “Management of the Fund,” the fee paid to Eaton Vance is calculated on the basis of the Fund’s average daily gross assets, including proceeds from the issuance of preferred shares and/or borrowings, so the fees will be higher when leverage is utilized. In this regard, holders of preferred shares do not bear the investment advisory fee. Rather, Common Shareholders bear the portion of the investment advisory fee attributable to the assets purchased with the proceeds of the preferred shares offering, which means that Common Shareholders effectively bear the entire advisory fee.

Financial leverage may also be achieved through the purchase of certain derivative instruments. The Fund’s use of derivative instruments exposes the Fund to special risks. See “Investment Objectives, Policies and Risks—Additional Investment Practices” and “Investment Objectives, Policies, and Risks—Risk Considerations.”

Management risk

The Fund is subject to management risk because it is an actively managed portfolio. Eaton Vance, Parametric and the individual portfolio managers will apply investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that these will produce the desired results.

Market disruption

Instability in the Middle East, the wars in Afghanistan, Iraq and Libya, geopolitical tensions elsewhere and terrorist attacks in the U.S. and around the world have resulted in market volatility and may have long-term effects on the U.S. and worldwide financial markets and may cause further economic uncertainties in the U.S. and worldwide. The Fund cannot predict the effects of significant future events on the global economy and securities markets. A similar disruption of the financial markets could impact interest rates, auctions, secondary trading, ratings, credit risk, inflation and other factors relating to the Common Shares.

Anti-takeover provisions

The Fund’s Agreement and Declaration of Trust includes provisions that could have the effect of limiting the ability of other persons or entities to acquire control of the Fund or to change the composition of its Board. See “Description of Capital Structure -- Anti-Takeover Provisions in the Declaration of Trust.”

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Summary of Fund Expenses

The purpose of the table below is to help you understand all fees and expenses that you, as a holder of Common Shares (“Common Shareholder”), would bear directly or indirectly. The table shows Fund expenses as a percentage of net assets attributable to Common Shares⁽¹⁾ for the year ended December 31 , 2016.


Common Shareholder transaction expenses
Sales load paid by you (as a percentage of offering price)	--⁽¹⁾
Offering expenses (as a percentage of offering price)	None⁽²⁾
Dividend reinvestment plan fees	None⁽³⁾

Annual expenses	Percentage of net assets attributable to Common Shares

Investment adviser fee	1.00%
Other expenses	0.12%
Total annual Fund operating expenses	1.12%

⁽¹⁾

If Common Shares are sold to or through underwriters, the Prospectus Supplement will set forth any applicable sales load.

⁽²⁾

The Adviser will pay the expenses of the Offering (other than the applicable commissions). Therefore Offering expenses are not included in the Summary of Fund Expenses. Offering expenses generally include, but are not limited to, the preparation, review and filing with the SEC of the Fund’s registration statement (including this Prospectus and the Statement of Additional Information), the preparation, review and filing of any associated marketing or similar materials, costs associated with the printing, mailing or other distribution of the Prospectus, Statement of Additional Information and/or marketing materials, associated filing fees, NYSE listing fees, and legal and auditing fees associated with the Offering.

⁽³⁾

You will be charged a $5.00 service charge and pay brokerage charges if you direct the plan agent to sell your Common Shares held in a dividend reinvestment account.

EXAMPLE

The following Example illustrates the expenses that Common Shareholders would pay on a $1,000 investment in Common Shares, assuming (i) total annual expenses of 1.12% of net assets attributable to Common Shares in years 1 through 10; (ii) a 5% annual return; and (iii) all distributions are reinvested at NAV:


1 Year	3 Years	5 Years	10 Years
$11	$36	$62	$136

The above table and example and the assumption in the example of a 5% annual return are required by regulations of the SEC that are applicable to all investment companies; the assumed 5% annual return is not a prediction of, and does not represent, the projected or actual performance of the Fund’s Common Shares. For more complete descriptions of certain of the Fund’s costs and expenses, see “Management of the Fund.” In addition, while the example assumes reinvestment of all dividends and distributions at NAV, participants in the Fund’s dividend reinvestment plan may receive Common Shares purchased or issued at a price or value different from NAV. See “Distributions” and “Dividend Reinvestment Plan.” The example does not include sales load or estimated offering costs, which would cause the expenses shown in the example to increase.

The example should not be considered a representation of past or future expenses, and the Fund’s actual expenses may be greater or less than those shown. Moreover, the Fund’s actual rate of return may be greater or less than the hypothetical 5% return shown in the example.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Financial Highlights and Investment Performance

FINANCIAL HIGHLIGHTS

This table details the financial performance of the Common Shares, including total return information showing how much an investment in the Fund has increased or decreased each period. This information has been audited by Deloitte & Touche LLP, an independent registered public accounting firm. The report of Deloitte & Touche LLP and the Fund’s financial statements are incorporated herein by reference and included in the Fund’s annual report, which is available upon request.

Selected data for a common share outstanding during the periods stated.


		Year Ended December 31,
	2016	2015	2014	2013	2012	2011	2010	2009	2008	2007
Net asset value – Beginning of year	$15.520	$16.310	$16.250	$14.900	$14.690	$15.020	$15.590	$13.650	$19.760	$20.320
Income (Loss) From Operations
Net investment income⁽¹⁾	$0.189	$0.198	$0.170	$0.184	$0.207	$0.188	$0.185	$0.223	$0.281	$0.230
Net realized and unrealized gain (loss)	1.087	0.308	1.186	2.462	1.299	0.778	1.045	3.517	(4.591)	1.010
Total income (loss) from operations	$1.276	$0.506	$1.356	$2.646	$1.506	$0.966	$1.230	$3.740	$(4.310)	$1.240
Less Distributions
From net investment income	$(0.177)	$(0.189)	$(0.165)	$(0.181)	$(0.202)	$(0.184)	$(0.183)	$(0.300)	$(0.280)	$(0.228)
From net realized gain	(0.482)	(0.368)	—	—	—	(0.126)	(0.040)	—	(0.470)	(0.693)
Tax return of capital	(0.637)	(0.739)	(1.131)	(1.115)	(1.094)	(0.986)	(1.577)	(1.500)	(1.050)	(0.879)
Total distributions	$(1.296)	$(1.296)	$(1.296)	$(1.296)	$(1.296)	$(1.296)	$(1.800)	$(1.800)	$(1.800)	$(1.800)
Net asset value – End of year	$15.500	$15.520	$16.310	$16.250	$14.900	$14.690	$15.020	$15.590	$13.650	$19.760
Market value – End of year	$16.520	$16.690	$15.900	$14.890	$14.030	$12.840	$14.410	$16.850	$12.530	$17.430
Total Investment Return on Net Asset Value⁽²⁾	8.68%	3.21%	8.94%	19.05%	11.25%	7.78%	8.82%	30.53%	(22.44)%⁽³⁾	6.62%
Total Investment Return on Market Value⁽²⁾	7.63%	13.92%	15.90%	15.85%	19.85%	(1.74)%	(3.47)%	53.69%	(19.29)%⁽³⁾	(9.43)%
Ratios/Supplemental Data
Net assets, end of year (000’s omitted)	$382,921	$382,897	$402,145	$400,633	$367,284	$362,180	$370,403	$383,356	$335,611	$485,633
Ratios (as a percentage of average daily net assets):
Expenses⁽⁴⁾	1.12%	1.11%	1.13%	1.14%	1.14%	1.15%	1.12%	1.12%	1.11%	1.11%
Net investment income	1.25%	1.23%	1.04%	1.17%	1.38%	1.30%	1.26%	1.61%	1.68%	1.15%
Portfolio Turnover	6%	7%	2%	2%	6%	20%	11%	34%	49%	35%

⁽¹⁾

Computed using average shares outstanding.

⁽²⁾

Returns are historical and are calculated by determining the percentage change in net asset value or market value with all distributions reinvested. Distributions are assumed to be reinvested at prices obtained under the Fund’s dividend reinvestment plan.

⁽³⁾

During the year ended December 31, 2008, the sub-adviser reimbursed the Fund for a realized loss on the disposal of an investment security which did not meet investment guidelines. The loss was less than $0.01 per share and had no effect on total return.

⁽⁴⁾

Excludes the effect of custody fee credits, if any, of less than 0.005%. Effective September 1, 2015, custody fee credits, which were earned on cash deposit balances, were discontinued by the custodian.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

TRADING AND NAV INFORMATION

The Fund’s common shares have traded both at a premium and a discount to NAV. The Fund cannot predict whether its shares will trade in the future at a premium or discount to NAV. The provisions of the 1940 Act generally require that the public offering price of common shares (less any underwriting commissions and discounts) must equal or exceed the NAV per share of a company’s common stock (calculated within 48 hours of pricing). The issuance of common shares may have an adverse effect on prices in the secondary market for the Fund’s common shares by increasing the number of common shares available, which may put downward pressure on the market price for the Fund’s common shares. Shares of common stock of closed-end investment companies frequently trade at a discount from NAV. See “Risk Considerations - Discount from or Premium to NAV”.

In addition, the Fund’s Board of Trustees has authorized the Fund to repurchase up to 10% of its outstanding common shares (as of the date of such authorization) in open-market transactions at a discount to NAV. The repurchase program does not obligate the Fund to purchase a specific amount of shares. The results of the repurchase program are disclosed in the Fund’s annual and semi-annual reports to shareholders. See “Description of Capital Structure – Repurchase of Common Shares and Other Discount Measures.”

The following table sets forth for each of the periods indicated the high and low closing market prices for Common Shares on the NYSE, and the corresponding NAV per share and the premium or discount to NAV per share at which the Fund’s Common Shares were trading as of such date.


	Market Price		NAV per Share on Date of Market Price High and Low		NAV Premium/(Discount) on Date of Market Price High and Low
Fiscal Quarter Ended	High	Low	High	Low	High	Low
12/31/2016	17.58	15.78	15.55	14.94	13.06%	5.62%
9/30/2016	16.58	15.82	15.39	15.34	7.73%	3.13%
6/30/2016	16.71	15.60	15.30	15.30	9.22%	1.96%
3/31/2016	16.48	13.85	15.36	14.14	7.29%	(2.05)%
12/31/2015	16.89	15.17	15.66	15.51	7.85%	(2.19)%
9/30/2015	16.81	14.94	16.31	14.77	3.07%	1.15%
6/30/2015	16.03	15.43	16.66	16.07	(3.78)%	(3.98)%
3/31/2015	16.43	15.39	16.54	15.91	(0.67)%	(3.27)%
12/31/2014	16.60	14.40	16.42	15.48	1.10%	(6.98)%
9/30/2014	16.41	15.41	16.55	16.17	(0.85)%	(4.70)%
6/30/2014	16.33	15.08	16.41	15.98	(0.49)%	(5.63)%
3/31/2014	15.62	14.77	16.12	16.22	(3.10)%	(8.94)%

The last reported sale price, NAV per share and percentage premium/(discount) to NAV per share of the Common Shares as of March 27, 2017 were $16.14, $15. 65 and 3.13 %, respectively. As of March 27, 2017 , the Fund had 24, 716,244 Common Shares outstanding and net assets of the Fund were $ 386,914,054 ..

The following table provides information about our outstanding Common Shares as of March 27, 2017:


Title of Class	Amount Authorized	Amount Held by the Fund for its Account	Amount Outstanding
Common Shares	Unlimited	0	24,716,244

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

The Fund

The Fund is a diversified, closed-end management investment company registered under the 1940 Act. The Fund was organized as a Massachusetts business trust on November 17, 2004 pursuant to an Agreement and Declaration of Trust governed by the laws of The Commonwealth of Massachusetts. The Fund’s principal office is located at Two International Place, Boston, Massachusetts 02110, and its telephone number is 1-800-262-1122.

Use of Proceeds

Subject to the remainder of this section, and unless otherwise specified in a Prospectus Supplement, the Fund currently intends to invest substantially all of the net proceeds of any sales of Common Shares pursuant to this Prospectus in accordance with the Fund’s investment objectives and policies. The Fund anticipates that it will be possible to invest the proceeds of the Offering consistent with the Fund’s investment objective and policies as soon as practicable, but in no event, assuming normal market conditions, later than three months after the receipt thereof. Pending such investment, the proceeds may be invested in short-term money market instruments, securities with remaining maturities of less than one year, cash and/or cash equivalents. A delay in the anticipated use of proceeds could lower returns and reduce the Fund’s distribution to Common Shareholders or result in a distribution consisting principally of a return of capital.

INVESTMENT OBJECTIVES, POLICIES AND RISKS

INVESTMENT OBJECTIVES

The Fund’s primary investment objective is to provide current income and gains, with a secondary objective of capital appreciation. In pursuing its investment objectives, the Fund will evaluate returns on an after-tax basis, seeking to minimize and defer shareholder federal income taxes. Under normal market conditions, the Fund’s investment program will consist primarily of (1) owning a diversified portfolio of common stocks that seeks to exceed the total return performance of the S&P 500 Composite Stock Price Index ® (the “S&P 500”) and (2) selling S&P 500 call options on a continuous basis on substantially the full value of its holdings of common stocks.

PRIMARY INVESTMENT POLICIES

General composition of the Fund

Under normal market conditions, the Fund invests at least 80% of its total assets in a diversified portfolio of common stocks that seeks to exceed the total return performance of the S&P 500. Due to tax considerations, the Fund intends to limit the overlap between its stock portfolio holdings (and any subset thereof) and the S&P 500 to less than 70% on an ongoing basis. The Fund invests primarily in common stocks of U.S. issuers. The Fund may invest up to 10% of its total assets in securities of foreign issuers, including American Depositary Receipts (“ADRs”), Global Depositary Receipts (“GDRs”) and European Depositary Receipts (“EDRs”). The Fund normally expects that its assets will be invested across a broad range of industries and market sectors. The Fund may not invest 25% or more of its total assets in the securities of issuers in any single industry or group of industries. The Fund may invest a portion of its assets in stocks of mid-capitalization companies. Eaton Vance generally considers mid-capitalization companies to be those companies having market capitalizations within the range of capitalizations for the S&P MidCap 400 Index (“S&P MidCap 400”). As of February 28, 2017 , the median market capitalization of companies in the S&P MidCap 400 was approximately $3. 9 billion.

The Fund seeks to generate current earnings in part by employing an options strategy of writing (selling) index call options on the S&P 500. The Fund expects to sell index call options on a continuous basis on substantially the full value of its holdings of common stocks. Under normal market conditions, at least 80% of the value of the Fund’s total assets will be subject to written index call options. Writing index call options involves a trade-off between the option premiums received and reduced participation in potential future stock price appreciation of the Fund’s portfolio of common stocks. Generally, the Fund intends to sell S&P 500 call options that are slightly “out-of-the-money,” meaning that option exercise prices generally will be slightly higher than the current level of the index at the time the options are written. The Fund seeks to generate current earnings from index option writing premiums and, to a lesser extent, from dividends on stocks held.

The Fund intends to sell S&P 500 call options that are exchange-listed and “European style,” meaning that the options may be exercised only on the expiration date of the option. Index options differ from options on individual securities in that index options (i) typically are settled in cash rather than by delivery of securities (meaning the exercise of an index option does not involve the actual purchase or sale of securities) and (ii) reflect price fluctuations in a group of securities or segments of the securities market rather than price fluctuations in a single security.

As the seller of S&P 500 call options, the Fund will receive cash (the premium) from options purchasers. The purchaser of an S&P 500 call option has the right to receive from the option seller any appreciation in the value of the S&P 500 over a fixed price (the exercise price) as of a specified date in the future (the option valuation date). The exercise-settlement value of the index is

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

calculated based on opening sales prices of the component index stocks on the option valuation date, which is the last business day before the expiration date. By writing S&P 500 call options, the Fund will, in effect, sell the potential appreciation in the value of the S&P 500 above the exercise price in exchange for the option premium received. If, at expiration, an S&P 500 call option sold by the Fund is exercised, the Fund will pay the purchaser the difference between the cash value of the S&P 500 and the exercise price of the option. The premium, the exercise price and the market value of the S&P 500 will determine the gain or loss realized by the Fund as the seller of the index call option.

The Fund expects to maintain high turnover in index call options, based on the Adviser’s intent to sell index call options on substantially the full value of its holdings of common stocks. For its stock holdings, the Fund’s annual portfolio turnover rate is expected to exceed that of the S&P 500 due to turnover in connection with the Fund’s tax loss harvesting, gain matching, dividend capture and other strategies. On an overall basis, the Fund’s annual turnover rate may exceed 100%. A high turnover rate (100% or more) necessarily involves greater trading costs to the Fund.

The Fund’s policies, under normal market conditions, that the Fund will invest at least 80% of its total assets in a diversified portfolio of common stocks that seeks to exceed the total return performance of the S&P 500 and that at least 80% of the value of the Fund’s total assets will be subject to written index call options on a continuous basis are non-fundamental policies and may be changed by the Fund’s Board without Common Shareholder approval following the provision of 60 days prior written notice to Common Shareholders.

The S&P 500 is an unmanaged index of 500 stocks maintained and published by Standard & Poor’s that is market-capitalization weighted and generally representative of the performance of larger stocks traded in the United States. It is not possible to invest directly in an index .. The Fund is not sponsored, endorsed, sold or promoted by Standard & Poor’s. Standard & Poor’s has not passed on the legality or suitability of, or the accuracy or adequacy of descriptions and disclosures relating to the Fund. Standard & Poor’s makes no representation regarding the advisability of investing in the Fund.

Investment strategy

Eaton Vance is responsible for managing the Fund’s overall investment strategy and executing the Fund’s options strategy. Eaton Vance also is responsible for providing research support to the Sub-Adviser and supervising the performance of the Sub-Adviser. Parametric is responsible for structuring and managing the Fund’s common stock portfolio, including tax-loss harvesting and other tax-management techniques, relying in part on the fundamental research and analytical judgments of the Adviser. The Fund’s investments are actively managed, and securities may be bought or sold on a daily basis. See “Management of the Fund.”

The Fund’s strategy consists of owning a portfolio of common stocks and selling covered call options (a “buy-write strategy”).

To avoid being subject to the “straddle rules” under federal income tax law, the Fund intends to maintain an overlap of less than 70% between its stock portfolio (and any subset thereof) and the S&P 500 on an ongoing basis. Under the “straddle” rules, “offsetting positions with respect to personal property” generally are considered to be straddles. In general, investment positions will be offsetting if there is a substantial diminution in the risk of loss from holding one position by reason of holding one or more other positions. The Fund expects that the index call options it writes will not be considered straddles because the Fund’s portfolio of common stocks will be sufficiently dissimilar from the components of the S&P 500 under applicable guidance established by the IRS. Under certain circumstances, however, the Fund may enter into options transactions or certain other investments that may constitute positions in a straddle. Parametric will consider a variety of factors in constructing and maintaining the Fund’s stock portfolio, including, but not limited to, stock performance ratings as determined by the Adviser, stock dividend yields, overlap between the stock portfolio holdings and the S&P 500, projected tracking of the stock portfolio versus the S&P 500, realization of loss harvesting opportunities and other tax management considerations. The Adviser’s evaluation of the future performance potential of individual stocks will be one among several considerations in portfolio construction and will not, on a standalone basis, be determinative of portfolio construction. The Adviser’s stock ratings will be based primarily on fundamental research.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

movements in portfolio stocks beyond certain levels. The Adviser intends to sell S&P 500 call options on substantially the full value of the Fund’s common stock holdings. The Adviser does not intend to sell index call options representing amounts greater than the value of the Fund’s common stock portfolio (i.e., take a “naked” position).

The foregoing policies relating to investment in common stocks and index options writing are the Fund’s primary investment policies. In addition to its primary investment policies, the Fund may invest to a limited extent in other types of securities and engage in certain other investment practices.

In addition to the intended strategy of selling index call options, the Fund may invest up to 20% of its total assets in other derivative instruments acquired for hedging, risk management and investment purposes (to gain exposure to securities, securities markets, markets indices and/or currencies consistent with its investment objectives and policies), provided that no more than 10% of the Fund’s total assets may be invested in such derivative instruments acquired for non-hedging purposes. Derivative instruments may be used in order to help protect against a decline in the value of its portfolio securities. Derivative instruments may also be used by the Fund to enhance returns or as a substitute for the purchase or sale of securities.

Tax-managed investing

Taxes are a major influence on the net after-tax returns that investors receive on their taxable investments. There are five potential sources of returns for a Common Shareholder: (1) appreciation or depreciation in the value of the Common Shares; (2) distributions of qualified dividend income; (3) distributions of other investment income and net short-term capital gains; (4) distributions of long-term capital gains (and long-term capital gains retained by the Fund); and (5) distributions of return of capital. These different sources of investment returns are subject to widely varying federal income tax treatment. Distributions of other investment income (i.e., non-qualified dividend income) and net realized short-term gains are taxed currently as ordinary income, at rates as high as 39.6%. Distributions of qualified dividend income and net realized long-term gains (whether distributed or retained by the Fund) are taxed at the rates applicable to long-term capital gain (currently at a maximum rate of 20% plus a 3.8% Medicare contribution tax for individuals and other noncorporate taxpayers). Generally, return from appreciation and depreciation in the value of Common Shares and distributions characterized as return of capital result in adjustment of a Common Shareholder’s federal income tax basis in his or her Common Shares and accordingly are not taxable until the Common Shareholder sells his or her Common Shares. Upon sale, a capital gain or loss equal to the difference between the net proceeds of such sale and the Common Shareholder’s adjusted tax basis is realized. Capital gain is considered long-term and is taxed at the rates applicable to long-term capital gain if the Common Shareholder has held his or her shares more than one year. Otherwise, capital gain is considered short-term gain and is taxed accordingly. The after-tax returns achieved by a Common Shareholder will be substantially influenced by the mix of different types of returns subject to varying federal income tax treatment.

In implementing the Fund’s investment strategy, the Adviser and Sub-Adviser intend to employ a variety of techniques and strategies designed to skew the mix of Fund returns to the types of returns that are most advantageously taxed, thereby seeking to minimize and defer the federal income taxes incurred by Common Shareholders in connection with their investment in the Fund. Such techniques and strategies are expected to include: (1) employing a call options strategy consisting of selling S&P 500 call options that qualify for treatment as “section 1256 contracts”, on which capital gains and losses are generally treated as 60% long-term and 40% short-term, regardless of holding period; (2) limiting the overlap of the Fund’s stock portfolio (and any subset thereof) versus the S&P 500 to less than 70% so that the Fund’s stock holdings and S&P 500 call options are not subject to the “straddle rules;” (3) engaging in a systematic program of tax-loss harvesting in the Fund’s stock portfolio, periodically selling stock positions that have depreciated in value to realize capital losses that can be used to offset capital gains realized by the Fund; and (4) managing the sale of appreciated stock positions so as to minimize the Fund’s net realized short-term capital gains in excess of net realized long-term capital losses. When an appreciated security is sold, the Fund intends to select for sale the share lots resulting in the most favorable tax treatment, generally those with holding periods sufficient to qualify for long-term capital gains treatment that have the highest cost basis.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

is (a) not eligible for the benefits of a comprehensive income tax treaty with the U.S. (with the exception of dividends paid on stock of such a foreign corporation readily tradable on an established securities market in the U.S.) or (b) treated as a passive foreign investment company. Payments in lieu of dividends, such as payments pursuant to securities lending arrangements, also do not qualify to be treated as qualified dividend income. In general, distributions of investment income reported by the Fund as derived from qualified dividend income will be treated as qualified dividend income by a shareholder taxed as an individual provided the shareholder meets the holding period and other requirements described above with respect to the Fund’s shares.

The Fund may seek to enhance the level of tax-advantaged dividend income it receives by emphasizing higher-yielding stocks in its stock portfolio and by engaging in dividend capture trading. In a dividend capture trade, the Fund sells a stock on or shortly after the stock’s ex-dividend date and uses the sale proceeds to purchase one or more other stocks that are expected to pay dividends before the next dividend payment on the stock being sold. Through this practice, the Fund may receive more dividend payments over a given time period than if it held a single stock. In order for dividends received by the Fund to qualify for favorable tax treatment, the Fund must comply with the holding period and other requirements set forth in the preceding paragraph. By complying with the applicable holding period and other requirements while engaging in dividend capture trading, the Fund may be able to enhance the level of tax-advantaged dividend income it receives because it will receive more dividend payments qualifying for favorable treatment during the same time period than if it simply held portfolio stocks. The use of dividend capture trading strategies will expose the Fund to increased trading costs and potentially higher short-term gain or loss.

To seek to protect against price declines in securities holdings with large accumulated gains, the Fund may use various hedging techniques (such as the sale of futures contracts on stocks and stock indices and options thereon, equity swaps, covered short sales and forward sales of stocks). By using these techniques rather than selling appreciated securities, the Fund can, within certain limitations, reduce its exposure to price declines in the securities without realizing substantial capital gains under current tax law. Derivative instruments may also be used by the Fund to enhance returns or as a substitute for the purchase or sale of securities. As a general matter, dividends received on hedged stock positions are characterized as ordinary income and are not eligible for favorable tax treatment. Dividends received on securities with respect to which the Fund is obligated to make related payments (pursuant to short sales or otherwise) will be treated as fully taxable ordinary income (i.e., income other than tax-advantaged dividends). In addition, use of derivatives may give rise to short-term capital gains and other income that would not qualify for favorable tax treatment. As indicated above, in addition to writing index call options, the Fund may invest up to 20% of its total assets in derivative instruments acquired for hedging, risk management and investment purposes (to gain exposure to securities, securities markets, markets indices and/or currencies consistent with its investment objectives and policies), provided that no more than 10% of the Fund’s total assets may be invested in such derivative instruments acquired for non-hedging purposes.

Common stocks

Under normal market conditions, the Fund will invest at least 80% of its total assets in a diversified portfolio of common stocks that seeks to exceed the total return performance of the S&P 500. Common stock represents an equity ownership interest in the issuing corporation. Holders of common stock generally have voting rights in the issuer and are entitled to receive common stock dividends when, as and if declared by the corporation’s board of directors. Common stock normally occupies the most subordinated position in an issuer’s capital structure. Returns on common stock investments consist of any dividends received plus the amount of appreciation or depreciation in the value of the stock.

Although common stocks have historically generated higher average returns than fixed-income securities over the long term and particularly during periods of high or rising concerns about inflation, common stocks also have experienced significantly more volatility in returns and may not maintain their real value during inflationary periods. An adverse event, such as an unfavorable earnings report, may depress the value of a particular common stock held by the Fund. Also, the prices of common stocks are sensitive to general movements in the stock market and a drop in the stock market may depress the price of common stocks to which the Fund has exposure. Common stock prices fluctuate for many reasons, including changes in investors’ perceptions of the financial condition of an issuer or the general condition of the relevant stock market, or when political or economic events affecting the issuers occur. In addition, common stock prices may be sensitive to rising interest rates as the costs of capital rise and borrowing costs increase.

Foreign securities

The Fund may invest up to 10% of its total assets in securities of issuers located in countries other than the United States. The Fund will not invest in issuers located in emerging market countries. Investment in securities of non-U.S. issuers involves special risks, including that non-U.S. issuers may be subject to less rigorous accounting and reporting requirements than U.S. issuers, less rigorous regulatory requirements, differing legal systems and laws relating to creditors’ rights, the potential inability to enforce legal judgments and the potential for political, social and economic adversity. The willingness and ability of sovereign issuers to pay principal and interest on government securities depends on various economic factors, including among others the issuer’s balance of payments, overall debt level, and cash flow considerations related to the availability of tax or other revenues to satisfy

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

the issuer’s obligations. The securities of some foreign issuers are less liquid and at times more volatile than securities of comparable U.S. issuers. Foreign settlement procedures and trade regulations may involve certain risks (such as delay in the payment or delivery of securities and interest or in the recovery of assets held abroad) and expenses not present in the settlement of domestic investments. Investments may include securities issued by the governments of lesser-developed countries, which are sometimes referred to as “emerging markets.” There may be a possibility of nationalization or expropriation of assets, imposition of currency exchange controls, confiscatory taxation, political or financial instability, armed conflict and diplomatic developments which could affect the value of the Fund’s investments in certain foreign countries. Foreign issuers may become subject to sanctions imposed by the United States or another country, which could result in the immediate freeze of the foreign issuers’ assets or securities. The imposition of such sanctions could impair the market value of the securities of such foreign issuers and limit the Fund’s ability to buy, sell, receive or deliver the securities. As an alternative to holding foreign-traded securities, the Fund may invest in dollar-denominated securities of foreign companies that trade on U.S. exchanges or in the U.S. over-the-counter market (including depositary receipts, which evidence ownership in underlying foreign securities). Dividends received with respect to stock of a foreign corporation may qualify for the reduced rates of federal income taxation applicable to qualified dividend income only if such corporation satisfies the requirements to be a “qualified foreign corporation.”

The Fund may invest in ADRs, EDRs and GDRs. ADRs, EDRs and GDRs are certificates evidencing ownership of shares of foreign issuers and are alternatives to purchasing directly the underlying foreign securities in their national markets and currencies. However, they continue to be subject to many of the risks associated with investing directly in foreign securities. These risks include foreign exchange risk as well as the political and economic risks of the underlying issuer’s country. ADRs, EDRs and GDRs may be sponsored or unsponsored. Unsponsored receipts are established without the participation of the issuer. Unsponsored receipts may involve higher expenses, may not pass through voting or other shareholder rights, and may be less liquid than sponsored receipts.

Index options generally

The Fund will pursue its objectives in part by selling S&P 500 call options on a continuous basis on substantially the full value of its common stock portfolio.

The Fund will sell S&P 500 index options that are exchange-listed and that are “European style,” meaning that the options may only be exercised on the expiration date of the option. Index options differ from options on individual securities in that index options (i) typically are settled in cash rather than by delivery of securities and (ii) reflect price fluctuations in a group of securities or segments of the securities market rather than price fluctuations in a single security. Option contracts are originated and standardized by the OCC. The Fund will sell S&P 500 call options that are generally issued, guaranteed and cleared by the OCC. S&P 500 options currently trade exclusively on the Chicago Board Options Exchange.

Selling index call options

The Fund’s index option strategy is designed to produce current cash flow from options premiums and to seek to moderate the volatility of the Fund’s returns. This index option strategy is of a hedging nature, and is not designed to speculate on equity market performance.

As the seller of S&P 500 call options, the Fund will receive cash (the premium) from the purchaser. The purchaser of the option has the right to any appreciation in the value of the S&P 500 over a fixed price (the exercise price) as of a specified date in the future (the option valuation date). Generally, the Fund intends to sell S&P 500 call options that are slightly “out-of-the-money” (i.e., the exercise price generally will be slightly above the current level of the S&P 500 when the option is sold). The Fund will, in effect, sell the potential appreciation in the value of the S&P 500 above the exercise price in exchange for the option premium received. If, at expiration, an S&P 500 call option sold by the Fund is exercised, the Fund will pay the purchaser the difference between the cash value of the S&P 500 and the exercise price of the option. The premium, the exercise price and the market value of the S&P 500 will determine the gain or loss realized by the Fund as the seller of the index call option.

Prior to expiration, the Fund may close an option position by making an offsetting market purchase of identical option contracts (same type, underlying index, exercise price and expiration). The cost of closing out transactions and payments in settlement of exercised options will reduce the net option premiums available for distribution to Common Shareholders by the Fund. The reduction in net option premiums due to a rise in stock prices should generally be offset, at least in part, by appreciation in the value of the Fund’s common stock portfolio and by the opportunity to realize higher premium income from selling new index options at higher exercise prices.

In certain extraordinary market circumstances, to limit the risk of loss on the Fund’s index option strategy, the Fund may enter into “spread” transactions by purchasing index call options with higher exercise prices than those of index call options written. The Fund will only engage in such transactions when Eaton Vance believes that certain extraordinary events temporarily have depressed equity prices and substantial short-term appreciation of such prices is expected. By engaging in spread transactions in

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

such circumstances the Fund will reduce the limitation imposed on its ability to participate in such recovering equity markets that exist if the Fund only writes index call options. The premiums paid to purchase such call options are expected to be lower than the premiums earned from the call options written at lower exercise prices. However, the payment of these premiums will reduce amounts available for distribution from the Fund’s option activity.

The Fund will sell only “covered” call options. An index call option is considered covered if the Fund maintains with its custodian assets determined to be liquid (in accordance with procedures established by the Board) in an amount equal to the contract value of the index. An index call option also is covered if the Fund holds a call on the same index as the call written where the exercise price of the call held is (i) equal to or less than the exercise price of the call written, or (ii) greater than the exercise price of the call written, provided the difference is maintained by the Fund in segregated assets determined to be liquid (in accordance with procedures established by the Board).

If an option written by the Fund expires unexercised, the Fund realizes on the expiration date a capital gain equal to the premium received by the Fund at the time the option was written. If an option written by the Fund is exercised, the Fund realizes on the expiration date a capital gain if the cash payment made by the Fund upon exercise is less than the premium received from writing the option and a capital loss if the cash payment made is more than the premium received. If a written option is repurchased, the Fund realizes upon the closing purchase transaction a capital gain if the cost of repurchasing the option is less than the premium received from writing the option and a capital loss if the cost of repurchasing the option is more than the premium received. Because exchange-listed S&P 500 options are “section 1256 contracts,” the Fund’s gains and losses thereon generally will be treated as 60% long-term and 40% short-term capital gain or loss, regardless of holding period. In addition, the Fund generally will be required to “mark to market” (i.e., treat as sold for fair market value) each outstanding index option position at the close of each taxable year (and on October 31 of each year for excise tax purposes). See “Federal Income Tax Matters.”

The principal factors affecting the market value of an option contract include supply and demand in the options market, interest rates, the current market price of the underlying index in relation to the exercise price of the option, the actual or perceived volatility associated with the underlying index and the time remaining until the expiration date. The premium received for an option written by the Fund is recorded as an asset of the Fund and its obligation under the option contract as an equivalent liability. The Fund then adjusts over time the liability as the market value of the option changes. The value of each written option will be marked to market daily and valued at the closing price on the exchange on which it is traded or, if not traded on an exchange or no closing price is available, at the mean between the last bid and asked prices or otherwise at fair value as determined by the Board of the Fund.

The transaction costs of buying and selling options consist primarily of commissions (which are imposed in opening, closing and exercise transactions), but may also include margin and interest costs in particular transactions. The impact of transaction costs on the profitability of a transaction may often be greater for options transactions than for transactions in the underlying securities because these costs are often greater in relation to options premiums than in relation to the prices of underlying securities. Transaction costs may be especially significant in option strategies calling for multiple purchases and sales of options over short periods of time or concurrently. Transaction costs associated with the Fund’s options strategy will vary depending on market circumstances and other factors.

The standard contract size for exchange-listed S&P 500 options is the index level multiplied by $100. There are three items needed to identify a particular S&P 500 option contract: (1) the expiration month, (2) the exercise (or strike) price and (3) the type (i.e., call or put). A call option whose exercise price is above the current price of the underlying index is called “out-of-the-money”, and a call option whose exercise price is below the current price of the underlying index is called “in-the-money.”

Writing S&P 500 call options can lower the variability of potential return outcomes and can enhance returns in three of four market performance scenarios (down, flat or moderately up). Only when the level of the S&P 500 at option expiration exceeds the sum of the premium received and the option exercise price would the buy-write strategy be expected to provide lower returns than the stock portfolio-only alternative. The amount of downside protection afforded by the buy-write strategy in declining market scenarios is limited, however, to the amount of option premium received. If the S&P 500 declines by an amount greater than the option premium, the buy-write strategy would generate an investment loss. The Fund’s returns from implementing a buy-write strategy using S&P 500 call options will also be substantially affected by the performance of the portfolio of stocks held versus the S&P 500.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

ADDITIONAL INVESTMENT PRACTICES

In addition to its primary investment strategies as described above, the Fund may engage in the following investment practices.

When-issued securities and forward commitments

Securities may be purchased on a “forward commitment” or “when-issued” basis (meaning securities are purchased or sold with payment and delivery taking place in the future beyond normal settlement times) in order to secure what is considered to be an advantageous price and yield at the time of entering into the transaction. However, the yield on a comparable security when the transaction is consummated may vary from the yield on the security at the time that the forward commitment or when-issued transaction was made. From the time of entering into the transaction until delivery and payment is made at a later date, the securities that are the subject of the transaction are subject to market fluctuations. In forward commitment or when-issued transactions, if the seller or buyer, as the case may be, fails to consummate the transaction, the counterparty may miss the opportunity of obtaining a price or yield considered to be advantageous. Forward commitment or when-issued transactions may be expected to occur a month or more before delivery is due. However, no payment or delivery is made until payment is received or delivery is made from the other party to the transaction. Forward commitment or when-issued transactions are not entered into for the purpose of investment leverage.

Illiquid securities

The Fund may invest up to 15% of its total assets in securities for which there is no readily available trading market or that are otherwise illiquid. Illiquid securities include securities legally restricted as to resale, such as commercial paper issued pursuant to Section 4(a)(2) of the Securities Act of 1933, as amended, and securities eligible for resale pursuant to Rule 144A thereunder. Section 4(a)(2) and Rule 144A securities may, however, be treated as liquid by the Adviser pursuant to procedures adopted by the Board, which require consideration of factors such as trading activity, availability of market quotations and number of dealers willing to purchase the security. If the Fund invests in Rule 144A securities, the level of portfolio illiquidity may be increased to the extent that eligible buyers become uninterested in purchasing such securities.

It may be difficult to sell illiquid securities at a price representing their fair value until such time as such securities may be sold publicly. Where registration is required, a considerable period may elapse between a decision by the Fund to sell the securities and the time when it would be permitted to sell. Thus, the Fund may not be able to obtain as favorable a price as that prevailing at the time of the decision to sell. The Fund may also acquire securities through private placements under which it may agree to contractual restrictions on the resale of such securities. Such restrictions might prevent their sale at a time when such sale would otherwise be desirable.

At times, a portion of the Fund’s assets may be invested in securities as to which the Fund, by itself or together with other accounts managed by the investment adviser and its affiliates, holds a major portion or all of such securities. Under adverse market or economic conditions or in the event of adverse changes in the financial condition of the issuer, the Fund could find it more difficult to sell such securities when the investment adviser believes it advisable to do so or may be able to sell such securities only at prices lower than if such securities were more widely held. It may also be more difficult to determine the fair value of such securities for purposes of computing the Fund’s net asset value.

Other derivative instruments

In addition to the intended strategy of selling index call options, the Fund may invest up to 20% of its total assets in other derivative instruments (which are instruments that derive their value from another instrument, security or index) acquired for hedging, risk management and investment purposes (to gain exposure to securities, securities markets, markets indices and/or currencies consistent with its investment objectives and policies), provided that no more than 10% of the Fund’s total assets may be invested in such derivative instruments acquired for non-hedging purposes. These strategies may be executed through the use of derivative contracts in the United States or abroad. As described more specifically below, the Fund may purchase and sell derivative contracts based on equity and fixed-income indices and other instruments, purchase and sell futures contracts and options thereon, and enter into various transactions such as swaps, caps, floors or collars. In addition, derivatives may also include new techniques, instruments or strategies that are permitted as regulatory changes occur. Derivative instruments may be used by the Fund to enhance returns or as a substitute for the purchase or sale of securities. The Fund’s transactions in derivative instruments involve a risk of loss or depreciation due to: unanticipated adverse changes in securities prices, interest rates, the other financial instruments’ prices; the inability to close out a position; default by the counterparty; imperfect correlation between a position and the desired hedge; tax constraints on closing out positions; and portfolio management constraints on securities subject to such transactions. The loss on derivative instruments (other than purchased options) may substantially exceed the Fund’s initial investment in these instruments. In addition, the Fund may lose the entire premium paid for purchased options that expire before they can be profitably exercised by the Fund. Transaction costs will be incurred in opening and closing positions in derivative instruments. There can be no assurance that the use of derivative instruments will be advantageous to the Fund.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Swaps

Swap contracts may be purchased or sold to hedge against fluctuations in securities prices, interest rates or market conditions, to change the duration of the overall portfolio, or to mitigate default risk. In a standard “swap” transaction, two parties agree to exchange the returns (or differentials in rates of return) to be exchanged or “swapped” between the parties, which returns are calculated with respect to a “notional amount,” i.e., the return on or increase in value of a particular dollar amount invested at a particular interest rate or in a “basket” of securities representing a particular index.

Interest rate swaps. The Fund will enter into interest rate and total return swaps only on a net basis, i.e., the two payment streams are netted out, with the Fund receiving or paying, as the case may be, only the net amount of the two payments. Interest rate swaps involve the exchange by the Fund with another party of their respective commitments to pay or receive interest (e.g., an exchange of fixed rate payments for floating-rate payments). The Fund will only enter into interest rate swaps on a net basis. If the other party to an interest rate swap defaults, the Fund’s risk of loss consists of the net amount of payments that the Fund is contractually entitled to receive. The net amount of the excess, if any, of the Fund’s obligations over its entitlements will be maintained in a segregated account by the Fund’s custodian. The Fund will not enter into any interest rate swap unless the claims-paying ability of the other party thereto is considered to be investment grade by the Adviser. If there is a default by the other party to such a transaction, the Fund will have contractual remedies pursuant to the agreements related to the transaction. These instruments are traded in the over-the-counter market.

The Fund may use interest rate swaps for risk management purposes only and not as a speculative investment and would typically use interest rate swaps to shorten the average interest rate reset time of the Fund’s holdings. Interest rate swaps involve the exchange by the Fund with another party of their respective commitments to pay or receive interest (e.g., an exchange of fixed rate payments for floating-rate payments). The use of interest rate swaps is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. If the Adviser is incorrect in its forecasts of market values, interest rates and other applicable factors, the investment performance of the Fund would be unfavorably affected.

Total return swaps. As stated above, the Fund will enter into total return swaps only on a net basis. Total return swaps are contracts in which one party agrees to make payments of the total return from the underlying asset(s), which may include securities, baskets of securities, or securities indices during the specified period, in return for payments equal to a fixed or floating-rate of interest or the total return from other underlying asset(s).

Futures and options on futures

The Fund may purchase and sell various kinds of financial futures contracts and options thereon to seek to hedge against changes in interest rates or for other risk management purposes. Futures contracts may be based on various debt securities and securities indices. Such transactions involve a risk of loss or depreciation due to unanticipated adverse changes in securities prices, which may exceed the Fund’s initial investment in these contracts. The Fund will only purchase or sell futures contracts or related options in compliance with the rules of the CFTC. These transactions involve transaction costs. There can be no assurance that Eaton Vance’s use of futures will be advantageous to the Fund. Sales of futures contracts and related options generally result in realization of short-term or long-term capital gain depending on the period for which the investment is held. To the extent that any futures contract or options on futures contract held by the Fund is a “section 1256 contract” under the Code, the contract will be marked-to-market annually and any gain or loss will be treated as 60% long-term and 40% short-term, regardless of the holding period for such contract.

Short sales

The Fund may sell a security short if it owns at least an equal amount of the security sold short or another security convertible or exchangeable for an equal amount of the security sold short without payment of further compensation (a short sale against-the-box). In a short sale against-the-box, the short seller is exposed to the risk of being forced to deliver stock that it holds to close the position if the borrowed stock is called in by the lender, which would cause gain or loss to be recognized on the delivered stock. The Fund expects normally to close its short sales against-the-box by delivering newly acquired stock.

Short sales against-the-box can be a tax-efficient alternative to the sale of an appreciated securities position. The ability to use short sales against-the-box as a tax-efficient management technique with respect to holdings of appreciated securities is limited to circumstances in which the hedging transaction is closed out not later than thirty days after the end of the Fund’s taxable year in which the transaction was initiated, and the underlying appreciated securities position is held unhedged for at least the next sixty days after the hedging transaction is closed. Not meeting these requirements would trigger the recognition of gain on the underlying appreciated securities position under the federal tax laws applicable to constructive sales.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Securities lending

The Fund may seek to earn income by lending portfolio securities to broker-dealers or other institutional borrowers. As with other extensions of credit, there are risks of delay in recovery or even loss of rights in the securities loaned if the borrower of the securities fails financially. Loans will be made only to organizations whose credit quality or claims paying ability is considered by the Adviser to be at least investment grade and when the expected returns, net of administrative expenses and any finders’ fees, justifies the attendant risk. Securities loans currently are required to be secured continuously by collateral in cash, cash equivalents (such as money market instruments) or other liquid securities held by the custodian and maintained in an amount at least equal to the market value of the securities loaned. The financial condition of the borrower will be monitored by the Adviser on an ongoing basis.

Borrowings

The Fund may borrow money to the extent permitted under the 1940 Act as interpreted, modified or otherwise permitted by the regulatory authority having jurisdiction. Although it does not currently intend to do so, the Fund may in the future from time to time borrow money to add leverage to the portfolio. The Fund may also borrow money for temporary administrative purposes or to meet temporary cash needs.

Reverse repurchase agreements

The Fund may enter into reverse repurchase agreements. Under a reverse repurchase agreement, the Fund temporarily transfers possession of a portfolio instrument to another party, such as a bank or broker-dealer, in return for cash. At the same time, the Fund agrees to repurchase the instrument at an agreed-upon time (normally within seven days) and price, which reflects an interest payment. The Fund may enter into such agreements when it is able to invest the cash acquired at a rate higher than the cost of the agreement, which would increase earned income.

When the Fund enters into a reverse repurchase agreement, any fluctuations in the market value of either the securities transferred to another party or the securities in which the proceeds may be invested would affect the market value of the Fund’s assets. As a result, such transactions may increase fluctuations in the market value of the Fund’s assets. While there is a risk that large fluctuations in the market value of the Fund’s assets could affect net asset value, this risk is not significantly increased by entering into reverse repurchase agreements, in the opinion of the Adviser. Because reverse repurchase agreements may be considered to be the practical equivalent of borrowing funds, they constitute a form of leverage and may be subject to leverage risks. The SEC views reverse repurchase transactions as collateralized borrowings. Such agreements will be treated as subject to investment restrictions regarding borrowings .. If the Fund reinvests the proceeds of a reverse repurchase agreement at a rate lower than the cost of the agreement, entering into the agreement will lower the Fund’s cash available for distribution.

Portfolio turnover

The Fund will buy and sell securities to seek to accomplish its investment objectives. Portfolio turnover generally involves expense to the Fund, including brokerage commissions and other transaction costs on the sale of securities and reinvestment in other securities. The Fund expects to maintain high turnover in index call options, based on the Adviser’s intent to sell index call options on substantially the full value of its holdings of common stocks. For its stock holdings, the Fund’s annual portfolio turnover rate is expected to exceed that of the S&P 500 due to turnover in connection with the Fund’s tax loss harvesting, gain matching, dividend capture and other strategies. On an overall basis, the Fund’s annual turnover rate may exceed 100%. A high turnover rate (100% or more) necessarily involves greater trading expenses to the Fund. The portfolio turnover rate for the Fund for the fiscal years ended December 31, 2016 and 2015 were 6% and 7 %, respectively.

RISK CONSIDERATIONS

Risk is inherent in all investing. Investing in any investment company security involves risk, including the risk that you may receive little or no return on your investment or even that you may lose part or all of your investment.

Discount from or premium to NAV

The Offering will be conducted only when Common Shares of the Fund are trading at a price equal to or above the Fund’s NAV per Common Share plus the per Common Share amount of commissions. As with any security, the market value of the Common Shares may increase or decrease from the amount initially paid for the Common Shares. The Fund’s Common Shares have traded both at a premium and at a discount relative to net asset value. The shares of closed-end management investment companies frequently trade at a discount from their NAV. This is a risk separate and distinct from the risk that the Fund’s NAV may decrease.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Secondary market for the Common Shares

Investment and market risk

Issuer risk

Equity risk

Risks of mid-cap companies

The Fund may make investments in stocks of companies whose market capitalization is considered middle sized or “mid-cap.” Mid-cap companies often are newer or less established companies than larger companies. Investments in mid-cap companies carry additional risks because earnings of these companies tend to be less predictable; they often have limited product lines, markets, distribution channels or financial resources; and the management of such companies may be dependent upon one person or a few key people. The market movements of equity securities of mid-cap companies may be more abrupt or erratic than the market movements of equity securities of larger, more established companies or the stock market in general. Historically, mid-cap companies have sometimes gone through extended periods when they did not perform as well as larger companies. In addition, equity securities of mid-cap companies generally are less liquid than those of larger companies. This means that the Fund could have greater difficulty selling such securities at the time and price that the Fund would like.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Risk of selling index call options

The Fund expects to sell S&P 500 call options on a continuous basis on substantially the full value of its holdings of common stocks. The purchaser of an index call option has the right to any appreciation in the value of the index over the exercise price of the call option as of the valuation date of the option. Because their exercise is settled in cash, sellers of index call options such as the Fund cannot provide in advance for their potential settlement obligations by acquiring and holding the underlying securities. The Fund intends to mitigate the risks of its written index call positions by holding a diversified portfolio of stocks similar to those on which the S&P 500 is based. However, the Fund does not intend to acquire and hold a portfolio containing exactly the same stocks as the S&P 500. Due to tax considerations, the Fund intends to limit the overlap between its stock portfolio holdings (and any subset thereof) and the S&P 500 to less than 70% on an ongoing basis. Consequently, the Fund bears the risk that the performance of the securities held will vary from the performance of the S&P 500. Index options written by the Fund will be priced on a daily basis. Their value will be affected primarily by changes in the price and dividend rates of the underlying common stocks in the S&P 500, changes in actual or perceived volatility of the S&P 500 and the remaining time to the options’ expiration. The trading price of S&P 500 options will also be affected by liquidity considerations and the balance of purchase and sale orders.

The trading price of options may be adversely affected if the market for such options becomes less liquid or smaller. The Fund may close out a call option by buying the option instead of letting it expire or be exercised. There can be no assurance that a liquid market will exist when the Fund seeks to close out a call option position by buying the option. Reasons for the absence of a liquid secondary market on an exchange include the following: (i) there may be insufficient trading interest in certain options; (ii) restrictions may be imposed by an exchange on opening transactions or closing transactions or both; (iii) trading halts, suspensions or other restrictions may be imposed with respect to particular classes or series of options; (iv) unusual or unforeseen circumstances may interrupt normal operations on an exchange; (v) the facilities of an exchange or the OCC may not at all times be adequate to handle current trading volume; or (vi) one or more exchanges could, for economic or other reasons, decide or be compelled to discontinue the trading of options (or a particular class or series of options) at some future date. If trading were discontinued, the secondary market on that exchange (or in that class or series of options) would cease to exist. However, outstanding options on that exchange that had been issued by the OCC as a result of trades on that exchange would continue to be exercisable in accordance with their terms.

The hours of trading for options may not conform to the hours during which common stocks held by the Fund are traded. To the extent that the options markets close before the markets for securities, significant price and rate movements can take place in the securities markets that would not be reflected concurrently in the options markets. Index call options are marked to market daily and their value is substantially affected by changes in the value and dividend rates of the securities represented in the underlying index, changes in interest rates, changes in the actual or perceived volatility of the associated index and the remaining time to the options’ expiration, as well as trading conditions in the options market.

Tax risk

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Foreign securities risk

Investments in foreign issuers could be affected by factors not present in the United States, including expropriation, armed conflict, confiscatory taxation, lack of uniform accounting and auditing standards, less publicly available financial and other information, potential difficulties in enforcing contractual obligations and the imposition of economic sanctions. Because foreign issuers may not be subject to uniform accounting, auditing and financial reporting standards, practices and requirements and regulatory measures comparable to those in the United States, there may be less publicly available information about such foreign issuers. Settlements of securities transactions in foreign countries are subject to risk of loss, may be delayed and are generally less frequent than in the United States, which could affect the liquidity of the Fund’s assets. As an alternative to holding foreign-traded securities, the Fund may invest in dollar-denominated securities of foreign companies that trade on U.S. exchanges or in the U.S. over-the- counter market (including depositary receipts, which evidence ownership in underlying foreign securities). Since the Fund may invest in securities denominated or quoted in currencies other than the U.S. dollar, the Fund will be affected by changes in foreign currency exchange rates (and exchange control regulations) which affect the value of investments held by the Fund and the accrued income and appreciation or depreciation of the investments in U.S. dollars. Changes in foreign currency exchange rates relative to the U.S. dollar will affect the U.S. dollar value of the Fund’s assets denominated in that currency and the Fund’s return on such assets as well as any temporary uninvested reserves in bank deposits in foreign currencies. In addition, the Fund will incur costs in connection with conversions between various currencies. Foreign securities may not be eligible for the reduced rate of taxation applicable to qualified dividend income.

Interest rate risk

Derivatives risk

In addition to writing index call options, the risks of which are described above, the Fund may invest up to 20% of its total assets in other derivative investments acquired for hedging, risk management and investment purposes, provided that no more than 10% of the Fund’s total assets may be invested in such derivative instruments acquired for non-hedging purposes. The Fund’s transactions in derivative instruments involve a risk of loss or depreciation due to: unanticipated adverse changes in securities prices, interest rates, the other financial instruments’ prices; the inability to close out a position; default by the counterparty; imperfect correlation between a position and the desired hedge; tax constraints on closing out positions; and portfolio management constraints on securities subject to such transactions. The loss on derivative instruments (other than purchased options) may substantially exceed the Fund’s initial investment in these instruments. In addition, the Fund may lose the entire premium paid for purchased options that expire before they can be profitably exercised by the Fund. Transaction costs will be incurred in opening and closing positions in derivative instruments. There can be no assurance that the use of derivative instruments will be advantageous to the Fund.

Liquidity risk

The Fund may invest up to 15% of its total assets in securities for which there is no readily available trading market or which are otherwise illiquid. The Fund may not be able readily to dispose of such securities at prices that approximate those at which the Fund could sell such securities if they were more widely traded and, as a result of such illiquidity, the Fund may have to sell other investments or engage in borrowing transactions if necessary to raise cash to meet its obligations. In addition, the limited liquidity could affect the market price of the securities, thereby adversely affecting the Fund’s net asset value and ability to make distributions, and at times may make the disposition of securities infeasible.

Inflation risk

Inflation risk is the risk that the value of assets or income from investment will be worth less in the future as inflation decreases the value of money. As inflation increases, the real value of the Common Shares and distributions thereon can decline.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Market price of Common Shares

As with any security, the market value of the Common Shares may increase or decrease from the amount initially paid for the Common Shares. The Fund’s Common Shares have traded both at a premium and at a discount relative to net asset value. The shares of closed-end management investment companies frequently trade at a discount from their NAV. This is a risk separate and distinct from the risk that the Fund’s NAV may decrease.

Financial leverage risk

Although the Fund has no current intention to do so, the Fund is authorized and reserves the flexibility to utilize leverage through the issuance of preferred shares and/or borrowings, including the issuance of debt securities. In the event that the Fund determines in the future to utilize investment leverage, there can be no assurance that such a leveraging strategy will be successful during any period in which it is employed. Leverage creates risks for Common Shareholders, including the likelihood of greater volatility of net asset value and market price of the Common Shares and the risk that fluctuations in distribution rates on any preferred shares or fluctuations in borrowing costs may affect the return to Common Shareholders. To the extent the returns derived from securities purchased with proceeds received from leverage exceeds the cost of leverage, the Fund’s distributions may be greater than if leverage had not been used. Conversely, if the returns from the securities purchased with such proceeds are not sufficient to cover the cost of leverage, the amount available for distribution to Common Shareholders will be less than if leverage had not been used. In the latter case, Eaton Vance, in its best judgment, may nevertheless determine to maintain the Fund’s leveraged position if it deems such action to be appropriate. The costs of an offering of preferred shares and/or a borrowing program would be borne by Common Shareholders and consequently would result in a reduction of the net asset value of Common Shares. In addition, the fee paid to Eaton Vance will be calculated on the basis of the Fund’s average daily gross assets, including proceeds from the issuance of preferred shares and/or borrowings, so the fees will be higher when leverage is utilized. In this regard, holders of preferred shares do not bear the investment advisory fee. Rather, Common Shareholders bear the portion of the investment advisory fee attributable to the assets purchased with the proceeds of the preferred shares offering.

Management risk

Market disruption

Anti-takeover provisions

The Fund’s Agreement and Declaration of Trust includes provisions that could limit the ability of other persons or entities to acquire control of the Fund or to change the composition of its Board. See “Description of Capital Structure -- Anti-Takeover Provisions in the Declaration of Trust.”

Management of the Fund

BOARD OF TRUSTEES

The management of the Fund, including general supervision of the duties performed by the Adviser under the Advisory Agreement (as defined below) and the Sub-Adviser under the Sub-Advisory Agreement (as defined below), is the responsibility of the Fund’s Board under the laws of The Commonwealth of Massachusetts and the 1940 Act.

THE ADVISER

Eaton Vance acts as the Fund’s investment adviser under an Investment Advisory Agreement (the “Advisory Agreement”). The Adviser’s principal office is located at Two International Place, Boston, MA 02110. Eaton Vance, its affiliates and predecessor companies have been managing assets of individuals and institutions since 1924 and of investment funds since 1931. As of January 31, 2017 , Eaton Vance and its affiliates managed approximately $ 363.7 billion of fund and separate account assets on behalf of clients, including approximately $ 99.6 billion in equity assets. Eaton Vance is a wholly-owned subsidiary of Eaton Vance Corp., a publicly-held holding company, which through its subsidiaries and affiliates engages primarily in investment management, administration and marketing activities.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Under the general supervision of the Fund’s Board, Eaton Vance is responsible for managing the Fund’s overall investment program and executing the Fund’s options strategy. Eaton Vance also is responsible for providing the Sub-Adviser with research support and supervising the performance of the Sub-Adviser. As described below under the caption “The Sub-Adviser,” Parametric will be responsible for structuring and managing the Fund’s common stock portfolio, including tax-loss harvesting and other tax-management techniques, relying in part on the fundamental research and analytical judgments of the Adviser. The Adviser will furnish to the Fund investment advice and office facilities, equipment and personnel for servicing the investments of the Fund. The Adviser will compensate all Trustees and officers of the Fund who are members of the Adviser’s organization and who render investment services to the Fund , and will also compensate all other Adviser personnel who provide research and investment services to the Fund. In return for these services, facilities and payments, the Fund has agreed to pay the Adviser as compensation under the Advisory Agreement an annual fee in the amount of 1.00% of the average daily gross assets of the Fund. Gross assets of the Fund means total assets of the Fund, including any form of investment leverage that the Fund may in the future determine to utilize, minus all accrued expenses incurred in the normal course of operations, but not excluding any liabilities or obligations attributable to any future investment leverage obtained through (i) indebtedness of any type (including, without limitation, borrowing through a credit facility/commercial paper program or the issuance of debt securities), (ii) the issuance of preferred shares or other similar preference securities, (iii) the reinvestment of collateral received for securities loaned in accordance with the Fund’s investment objectives and policies and/or (iv) any other means. During any future periods in which the Fund is using leverage, the fees paid to Eaton Vance for investment advisory services will be higher than if the Fund did not use leverage because the fees paid will be calculated on the basis of the Fund’s gross assets, including proceeds from any borrowings and from the issuance of preferred shares. The Fund is responsible for all expenses not expressly stated by another party (such as the expenses required to be paid pursuant to an agreement with the investment adviser or administrator).

Michael A. Allison is responsible for managing the Fund’s overall investment program and executing the Fund’s options strategy, and also provides the Sub-Adviser with research support and supervises the performance of the Sub-Adviser.

Mr. Allison is a Vice President of Eaton Vance, is a member of Eaton Vance’s Equity Strategy Committee and has been portfolio manager of the Fund since June 2015. Mr. Allison has managed other Eaton Vance portfolios for more than five years.

THE SUB-ADVISER

Eaton Vance has engaged its affiliate Parametric as a sub-adviser to the Fund. Parametric is responsible for structuring and managing the Fund’s common stock portfolio, including tax-loss harvesting and other tax-management techniques, relying in part on the fundamental research and analytical judgments of the Adviser. Parametric’s principal office is located at 1918 Eighth Avenue, Suite 3100, Seattle, WA 98101. Parametric is a Seattle, Washington based investment manager that has been providing investment advisory services since its formation in 1987. Parametric managed approximately $ 185.9 billion in assets as of January 31, 2017 ..

Under the terms of the Sub-Advisory Agreement (a “Sub-Advisory Agreement”) between Eaton Vance and Parametric, Eaton Vance (and not the Fund) pays Parametric a portion of the advisory fee for sub-advisory services provided to the Fund. Pursuant to the terms of the Advisory Agreement, Eaton Vance, upon approval by the Board, may terminate the Sub-Advisory Agreement, and Eaton Vance may assume full responsibility for the services provided by Parametric without the need for approval by shareholders of the Fund.

Thomas Seto is the Parametric portfolio manager responsible for the day-to-day structuring and management of the Fund’s common stock portfolio. Mr. Seto manages two other Eaton Vance closed-end investment companies that utilize a buy-write investment strategy.

Mr. Seto is Head of Investment Management at Parametric’s Seattle Investment Center and was previously Director of Portfolio Management at Parametric for more than five years. Mr. Seto has been a portfolio manager of the Fund since June 2005 and has managed other Eaton Vance portfolios for more than five years.

The Fund, the Adviser and the Sub-Adviser have adopted codes of ethics relating to personal securities transactions (the “Codes of Ethics”). The Codes of Ethics permit Adviser and Sub-Adviser personnel to invest in securities (including securities that may be purchased or held by the Fund) for their own accounts, subject to certain pre-clearance, reporting and other restrictions and procedures contained in such Codes of Ethics.

Additional Information Regarding Portfolio Managers

The Statement of Additional Information provides additional information about the portfolio managers’ compensation, other accounts managed by the portfolio managers, and the portfolio managers’ ownership of securities in the Fund. The Statement of Additional Information is available free of charge by calling 1-800- 262-1122 or by visiting the Fund’s website at http://www.eatonvance.com. The information contained in, or that can be accessed through, the Fund’s website is not part of this prospectus or the Statement of Additional Information.

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THE ADMINISTRATOR

Eaton Vance serves as administrator of the Fund. Under an Amended and Restated Administrative Services Agreement with the Fund (the “Administration Agreement”), Eaton Vance is responsible for managing the business affairs of the Fund, subject to the supervision of the Fund’s Board. Eaton Vance furnishes to the Fund all office facilities, equipment and personnel for administering the affairs of the Fund. Eaton Vance’s administrative services include recordkeeping, preparation and filing of documents required to comply with federal and state securities laws, supervising the activities of the Fund’s custodian and transfer agent, providing assistance in connection with the Board and shareholders’ meetings, providing service in connection with any repurchase offers and other administrative services necessary to conduct the Fund’s business. Eaton Vance currently receives no compensation for providing administrative services to the Fund.

Plan of Distribution

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The Fund or one of the Fund’s affiliates may loan or pledge Common Shares to a financial institution or other third party that in turn may sell Common Shares using this Prospectus. Such financial institution or third party may transfer its short position to investors in Common Shares or in connection with a simultaneous Offering of other Common Shares offered by this Prospectus or otherwise.

Distributions

The Fund distinguishes between distributions on a tax basis and a financial reporting basis. Accounting principles generally accepted in the United States of America require that only distributions in excess of tax basis earnings and profits be reported in the financial statements as a return of capital. Permanent differences between book and tax accounting relating to distributions are reclassified to paid-in capital. For tax purposes, distributions from short-term capital gains are considered to be from ordinary income.

Common Shareholders may elect automatically to reinvest some or all of their distributions in additional Common Shares under the Fund’s dividend reinvestment plan. See “Dividend Reinvestment Plan.”

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Federal Income Tax Matters

The Fund intends to elect to be treated and to qualify each year as a regulated investment company (“RIC”) under the Internal Revenue Code of 1986, as amended (the “Code”). Accordingly, the Fund intends to satisfy certain requirements relating to sources of its income and diversification of its assets and to distribute substantially all of its net income (including both investment company taxable income and net tax-exempt interest income) and net short-term and long-term capital gains (after reduction by any available capital loss carryforwards) in accordance with the timing requirements imposed by the Code, so as to maintain its RIC status and to avoid paying federal income or excise tax thereon. If it qualifies for treatment as a RIC and satisfies the above-mentioned distribution requirements, the Fund will not be subject to federal income tax on income paid to its shareholders in the form of dividends or capital gains distributions.

To qualify as a RIC for federal income tax purposes, the Fund must derive at least 90% of its annual gross income from dividends, interest, payments with respect to securities loans, gains from the sale or other disposition of stock, securities or foreign currencies, or other income (including, but not limited to, gains from options, futures or forward contracts) derived with respect to its business of investing in stock, securities and currencies, and net income derived from an interest in a qualified publicly traded partnership. The Fund must also distribute to its shareholders at least the sum of 90% of its investment company taxable income and 90% of its net tax-exempt interest income for each taxable year.

If the Fund does not qualify as a RIC for any taxable year, the Fund’s taxable income will be subject to corporate income taxes, and all distributions from earnings and profits, including distributions of net capital gain (if any), will be taxable to the shareholder as ordinary income. Such distributions will be treated as qualified dividend income with respect to shareholders who are individuals and will be eligible for the dividends received deduction in the case of shareholders taxed as corporations, provided certain holding period requirements are met. In order to requalify for taxation as a RIC, the Fund may be required to recognize unrealized gains, pay substantial taxes and interest, and make substantial distributions.

At least annually, the Fund intends to distribute any net capital gain (which is the excess of net long-term capital gain over net short-term capital loss) or, alternatively, to retain all or a portion of the year’s net capital gain and pay federal income tax on the retained gain. As provided under federal tax law, Common Shareholders of record as of the end of the Fund’s taxable year will include their attributable share of the retained gain in their income for the year as long-term capital gain (regardless of holding period in the Common Shares) and will be entitled to a tax credit or refund for the tax paid on their behalf by the Fund. Common Shareholders of record for the retained capital gain will also be entitled to increase their tax basis in their Common Shares by 65 percent of the allocated gain. Distributions of the Fund’s net capital gain (“capital gain distributions”), if any, are taxable to Common Shareholders as long-term capital gain, regardless of their holding period in the Common Shares. Distributions of gains from the sale of investments that the Fund owned for one year or less will be taxable as ordinary income.

If, for any calendar year, the Fund’s total distributions exceed the Fund’s current and accumulated earnings and profits, the excess will be treated as a tax-free return of capital to each Common Shareholder (up to the amount of the Common Shareholder’s basis in his or her Common Shares) and thereafter as gain from the sale of Common Shares (assuming the Common Shares are held as a capital asset). The amount treated as a tax-free return of capital will reduce the Common Shareholder’s adjusted basis in his or her Common Shares, thereby increasing his or her potential gain or reducing his or her potential loss on the subsequent sale or other disposition of his or her Common Shares. See below for a summary of the maximum tax rates applicable to long-term capital gain (including capital gain distributions). A corporation that owns Fund shares generally will not be entitled to the dividends received deduction with respect to all (or any prescribed percentage) of the distributions it receives from the Fund. Fund distributions that are attributable to qualified dividend income received by the Fund from certain domestic corporations may be designated by the Fund as being eligible for the dividends received deduction.

Certain of the Fund’s investment practices are subject to special and complex federal income tax provisions that may, among other things, (i) convert dividends that would otherwise constitute qualified dividend income into ordinary income, (ii) treat dividends that would otherwise be eligible for the corporate dividends received deduction as ineligible for such treatment, (iii) disallow, suspend or otherwise limit the allowance of certain losses or deductions, (iv) convert long-term capital gain into short-term capital gain or ordinary income, (v) convert an ordinary loss or deduction into a capital loss (the deductibility of which is more limited), (vi) cause the Fund to recognize income or gain without a corresponding receipt of cash, (vii) adversely affect the time as to when a purchase or sale of stock or securities is deemed to occur and (viii) adversely alter the characterization of

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certain complex financial transactions. While it may not always be successful in doing so, the Fund will seek to avoid or minimize any adverse tax consequences of its investment practices.

In the case of Fund transactions involving S&P 500 call options (or other listed options on broad-based securities indices), Code Section 1256 generally will require any gain or loss arising from the lapse, closing out or exercise of such positions to be treated as 60% long-term and 40% short-term capital gain or loss. In addition, the Fund generally will be required to “mark to market” (i.e., treat as sold for fair market value) each outstanding index option position at the close of each taxable year (and on October 31 of each year for excise tax purposes). If a Section 1256 Contract held by the Fund at the end of a taxable year is sold in the following year, the amount of any gain or loss realized on such sale will be adjusted to reflect the gain or loss previously taken into account under the “mark to market” rules. In addition to most index call options, Section 1256 Contracts include certain other options contracts, certain regulated futures contracts and certain other financial contracts.

The Code contains special rules that apply to “straddles,” defined generally as the holding of “offsetting positions with respect to personal property.” For example, the straddle rules normally apply when a taxpayer holds stock and an offsetting option with respect to such stock or substantially identical stock or securities. In general, investment positions will be offsetting if there is a substantial diminution in the risk of loss from holding one position by reason of holding one or more other positions. The Fund expects that the index call options it writes will not be considered straddles for this purpose because the Fund’s portfolio of common stocks will be sufficiently dissimilar from the components of the S&P 500 under applicable guidance established by the IRS. Under certain circumstances, however, the Fund may enter into options transactions or certain other investments that may constitute positions in a straddle. If two or more positions constitute a straddle, recognition of a realized loss from one position must generally be deferred to the extent of unrecognized gain in an offsetting position. In addition, long-term capital gain may be recharacterized as short-term capital gain, or short-term capital loss as long-term capital loss. Interest and other carrying charges allocable to personal property that is part of a straddle are not currently deductible but must instead be capitalized. Similarly, “wash sale” rules apply to prevent the recognition of loss by the Fund from the disposition of stock or securities at a loss in a case in which identical or substantially identical stock or securities (or an option to acquire such property) is or has been acquired within a prescribed period.

The Code allows a taxpayer to elect to offset gains and losses from positions that are part of a “mixed straddle.” A “mixed straddle” is any straddle in which one or more but not all positions are section 1256 contracts. The Fund may be eligible to elect to establish one or more mixed straddle accounts for certain of its mixed straddle trading positions. The mixed straddle account rules require a daily “marking to market” of all open positions in the account and a daily netting of gains and losses from all positions in the account. At the end of a taxable year, the annual net gains or losses from the mixed straddle account are recognized for tax purposes. The net capital gain or loss is treated as 60% long-term and 40% short-term capital gain or loss if attributable to the section 1256 contract positions, or all short-term capital gain or loss if attributable to the non-section 1256 contract positions.

The Fund may recognize gain (but not loss) from a constructive sale of certain “appreciated financial positions” if the Fund enters into a short sale, offsetting notional principal contract, or a forward contract transaction with respect to the appreciated position or substantially identical property. Appreciated financial positions subject to this constructive sale treatment include interests (including options and forward contracts and short sales) in stock and certain other instruments. Constructive sale treatment does not apply if the transaction is closed out not later than thirty days after the end of the taxable year in which the transaction was initiated, and the underlying appreciated securities position is held unhedged for at least the next sixty days after the hedging transaction is closed.

Gain or loss from a short sale of property is generally considered as capital gain or loss to the extent the property used to close the short sale constitutes a capital asset in the Fund’s hands. Except with respect to certain situations where the property used to close a short sale has a long-term holding period on the date the short sale is entered into, gains on short sales generally are short-term capital gains. A loss on a short sale will be treated as a long-term capital loss if, on the date of the short sale, “substantially identical property” has been held by the Fund for more than one year. In addition, entering into a short sale may result in suspension of the holding period of “substantially identical property” held by the Fund.

Gain or loss on a short sale will generally not be realized until such time as the short sale is closed. However, as described above in the discussion of constructive sales, if the Fund holds a short sale position with respect to securities that have appreciated in value, and it then acquires property that is the same as or substantially identical to the property sold short, the Fund generally will recognize gain on the date it acquires such property as if the short sale were closed on such date with such property. Similarly, if the Fund holds an appreciated financial position with respect to securities and then enters into a short sale with respect to the same or substantially identical property, the Fund generally will recognize gain as if the appreciated financial position were sold at its fair market value on the date it enters into the short sale. The subsequent holding period for any appreciated financial position that is subject to these constructive sale rules will be determined as if such position were acquired on the date of the constructive sale.

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Certain dividend distributions paid by the Fund (whether paid in cash or reinvested in additional Common Shares) to individual taxpayers are taxed at rates applicable to net long-term capital gains (20%, 15% or 0%, depending on an individual’s tax bracket). This tax treatment applies only if certain holding period and other requirements are satisfied by the Common Shareholder and the dividends are attributable to qualified dividend income received by the Fund itself. For this purpose, “qualified dividend income” means dividends received by the Fund from U.S. corporations and “qualified foreign corporations,” provided that the Fund satisfies certain holding period and other requirements in respect of the stock of such corporations. In order for qualified dividends paid by the Fund to a Common Shareholder to be taxable at long-term capital gains rates, the Common Shareholder must hold his or her Common Shares for more than 60 days during the 121-day period surrounding the ex-dividend date. For the Fund to receive tax-advantaged dividend income, the Fund must hold stock paying qualified dividend income for more than 60 days during the 121-day period beginning 60 days before the ex-dividend date (or more than 90 days during the associated 181-day period, in the case of certain preferred stocks). In addition, the Fund cannot be obligated to make related payments (pursuant to a short sale or otherwise) with respect to positions in any security that is substantially similar or related property with respect to such stock. Gains on option positions treated as short-term and other short-term gains, interest income and non-qualified dividends are not eligible for the lower tax rate. There can be no assurance as to what portion of the Fund’s dividend distributions will qualify for favorable treatment. The Fund’s investment program and the tax treatment of Fund distributions may be affected by IRS interpretations of the Code and future changes in tax laws and regulations.

The Fund will inform Common Shareholders of the source and tax status of all distributions promptly after the close of each calendar year.

Selling Common Shareholders will generally recognize gain or loss in an amount equal to the difference between the Common Shareholder’s adjusted tax basis in the Common Shares sold and the sale proceeds. If the Common Shares are held as a capital asset, the gain or loss will be a capital gain or loss. The maximum tax rate applicable to net capital gains recognized by individuals and other non-corporate taxpayers is (i) the same as the maximum ordinary income tax rate for gains recognized on the sale of capital assets held for one year or less, or (ii) 20% for gains recognized on the sale of capital assets held for more than one year (as well as any capital gain distributions) (15% or 0% for individuals in certain tax brackets). Any loss on a disposition of Common Shares held for six months or less will be treated as a long-term capital loss to the extent of any capital gain distributions received with respect to those Common Shares. For purposes of determining whether Common Shares have been held for six months or less, the holding period is suspended for any periods during which the Common Shareholder’s risk of loss is diminished as a result of holding one or more other positions in substantially similar or related property, or through certain options or short sales. Any loss realized on a sale or exchange of Common Shares will be disallowed to the extent those Common Shares are replaced by other Common Shares within a period of 61 days beginning 30 days before and ending 30 days after the date of disposition of the Common Shares (whether through the reinvestment of distributions or otherwise). In that event, the basis of the replacement Common Shares will be adjusted to reflect the disallowed loss.

An investor should be aware that, if Common Shares are purchased shortly before the record date for any taxable distribution (including a capital gain distribution), the purchase price likely will reflect the value of the distribution and the investor then would receive a taxable distribution that is likely to reduce the trading value of such Common Shares, in effect resulting in a taxable return of some of the purchase price. Taxable distributions to certain individuals and certain other non-corporate Common Shareholders, including those who have not provided their correct taxpayer identification number and other required certifications, may be subject to “backup” federal income tax withholding at the fourth lowest rate of tax applicable to a single individual (currently 28%).

An investor should also be aware that the benefits of the reduced tax rate applicable to long-term capital gains and qualified dividend income may be impacted by the application of the alternative minimum tax to individual shareholders.

Certain foreign entities including foreign entities acting as intermediaries may be subject to a 30% withholding tax on dividend income paid and, after December 31, 2018, on gross redemption proceeds paid under the Foreign Account Tax Compliance Act (“FATCA”). To avoid withholding, foreign financial institutions subject to FATCA must agree to disclose to the relevant revenue authorities certain information regarding their direct and indirect U.S. owners and other foreign entities must certify certain information regarding their direct and indirect U.S. owners to the Fund. For more detailed information regarding FATCA withholding and compliance, please refer to the Statement of Additional Information.

Eaton Vance Tax-Managed Buy-Write Income Fund

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The foregoing briefly summarizes some of the important federal income tax consequences to Common Shareholders of investing in Common Shares, reflects the federal tax law as of the date of this Prospectus and does not address special tax rules applicable to certain types of investors, such as corporate and foreign investors. Unless otherwise noted, this discussion assumes that an investor is a U.S. person and holds Common Shares as a capital asset. This discussion is based upon current provisions of the Code, the regulations promulgated thereunder and judicial and administrative ruling authorities, all of which are subject to change or differing interpretations by the courts or the IRS retroactively or prospectively. Investors should consult their tax advisors regarding other federal, state or local tax considerations that may be applicable in their particular circumstances, as well as any proposed tax law changes.

Dividend Reinvestment Plan

The Fund offers a dividend reinvestment plan (the “Plan”), pursuant to which a Common Shareholder may elect to have distributions automatically reinvested in Common Shares of the Fund. You may elect to participate in the Plan by completing the Dividend Reinvestment Plan Application Form. If you do not participate, you will receive all Fund distributions in cash paid by check mailed directly to you by American Stock Transfer & Trust Company, LLC (“AST” or “Plan Agent”), as dividend paying agent. On the distribution payment date, if the net asset value per Common Share is equal to or less than the market price per Common Share plus estimated brokerage commissions, then new Common Shares will be issued. The number of Common Shares shall be determined by the greater of the net asset value per Common Share or 95% of the market price. Otherwise, Common Shares generally will be purchased on the open market by the Plan Agent. Distributions subject to income tax (if any) are taxable whether or not shares are reinvested.

If your shares are in the name of a brokerage firm, bank, or other nominee, you can ask the firm or nominee to participate in the Plan on your behalf. If the nominee does not offer the Plan, you will need to request that your shares be re-registered in your name with the Fund’s transfer agent, AST, or you will not be able to participate.

The Plan Agent’s service fee for handling distributions will be paid by the Fund. Each participant will be charged their pro rata share of brokerage commissions on all open-market purchases.

Plan participants may withdraw from the Plan at any time by writing to the Plan Agent at the address noted on the following page. If you withdraw, you will receive shares in your name for all Common Shares credited to your account under the Plan. If a participant elects by written notice to the Plan Agent to have the Plan Agent sell part or all of his or her Common Shares and remit the proceeds, the Plan Agent is authorized to deduct a $5.00 fee plus brokerage commissions from the proceeds.

Any inquiries regarding the Plan can be directed to the Plan Agent, AST, at 1-866-439-6787.

Description of Capital Structure

The Fund is an unincorporated business trust established under the laws of The Commonwealth of Massachusetts by an Agreement and Declaration of Trust dated and filed with the Secretary of The Commonwealth on November 17, 2004 (the “Declaration of Trust”). The Declaration of Trust provides that the Board may authorize separate classes of shares of beneficial interest. The Board has authorized an unlimited number of Common Shares. The Fund intends to hold annual meetings of Common Shareholders in compliance with the requirements of the NYSE.

COMMON SHARES

The Declaration of Trust permits the Fund to issue an unlimited number of full and fractional Common Shares. Each Common Share represents an equal proportionate interest in the assets of the Fund with each other Common Share in the Fund. Common Shareholders will be entitled to the payment of distributions when, as and if declared by the Board. The 1940 Act or the terms of any future borrowings or issuance of preferred shares may limit the payment of distributions to the Common Shareholders. Each whole Common Share shall be entitled to one vote as to matters on which it is entitled to vote pursuant to the terms of the Declaration of Trust on file with the SEC. Upon liquidation of the Fund, after paying or adequately providing for the payment of all liabilities of the Fund and the liquidation preference with respect to any outstanding preferred shares, and upon receipt of such releases, indemnities and refunding agreements as they deem necessary for their protection, the Board may distribute the remaining assets of the Fund among the Common Shareholders. The Declaration of Trust provides that Common Shareholders are not liable for any liabilities of the Fund and permits inclusion of a clause to that effect in every agreement entered into by the Fund and, in coordination with the Fund’s By-laws, indemnifies shareholders against any such liability. Although shareholders of an unincorporated business trust established under Massachusetts law may, in certain limited circumstances, be held personally liable for the obligations of the business trust as though they were general partners, the provisions of the Fund’s Declaration of Trust and By-laws described in the foregoing sentence make the likelihood of such personal liability remote.

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The Fund has no current intention to issue preferred shares or to borrow money. However, if at some future time there are any borrowings or preferred shares outstanding, the Fund may not be permitted to declare any cash distribution on its Common Shares, unless at the time of such declaration, (i) all accrued distributions on preferred shares or accrued interest on borrowings have been paid and (ii) the value of the Fund’s total assets (determined after deducting the amount of such distribution), less all liabilities and indebtedness of the Fund not represented by senior securities, is at least 300% of the aggregate amount of such securities representing indebtedness and at least 200% of the aggregate amount of securities representing indebtedness plus the aggregate liquidation value of the outstanding preferred shares. In addition to the requirements of the 1940 Act, the Fund may be required to comply with other asset coverage requirements as a condition of the Fund obtaining a rating of preferred shares from a nationally recognized statistical rating agency (a “Rating Agency”). These requirements may include an asset coverage test more stringent than under the 1940 Act. This limitation on the Fund’s ability to make distributions on its Common Shares could in certain circumstances impair the ability of the Fund to maintain its qualification for taxation as a regulated investment company for federal income tax purposes. If the Fund were in the future to issue preferred shares or borrow money, it would intend, however, to the extent possible to purchase or redeem preferred shares or reduce borrowings from time to time to maintain compliance with such asset coverage requirements and may pay special distributions to the holders of the preferred shares in certain circumstances in connection with any potential impairment of the Fund’s status as a regulated investment company. See “Federal Income Tax Matters.” Depending on the timing of any such redemption or repayment, the Fund may be required to pay a premium in addition to the liquidation preference of the preferred shares to the holders thereof.

The Fund has no present intention of offering additional Common Shares, except as described herein. Other offerings of its Common Shares, if made, will require approval of the Board. Any additional offering will not be sold at a price per Common Share below the then current net asset value (exclusive of underwriting discounts and commissions) except in connection with an offering to existing Common Shareholders or with the consent of a majority of the outstanding Common Shares. The Common Shares have no preemptive rights.

The Fund generally will not issue Common Share certificates. However, upon written request to the Fund’s transfer agent, a share certificate will be issued for any or all of the full Common Shares credited to an investor’s account. Common Share certificates that have been issued to an investor may be returned at any time.

REPURCHASE OF COMMON SHARES AND OTHER DISCOUNT METHODS

Because shares of closed-end management investment companies frequently trade at a discount to their net asset values, the Board has determined that from time-to-time it may be in the interest of Common Shareholders for the Fund to take corrective actions to reduce trading discounts in the Common Shares. The Board, in consultation with Eaton Vance, will review at least annually the possibility of open market repurchases and/or tender offers for the Common Shares and will consider such factors as the market price of the Common Shares, the net asset value of the Common Shares, the liquidity of the assets of the Fund, the effect on the Fund’s expenses, whether such transactions would impair the Fund’s status as a regulated investment company or result in a failure to comply with applicable asset coverage requirements, general economic conditions and such other events or conditions that may have a material effect on the Fund’s ability to consummate such transactions. There are no assurances that the Board will, in fact, decide to undertake either of these actions or, if undertaken, that such actions will result in the Common Shares trading at a price equal to or approximating their net asset value. In recognition of the possibility that the Common Shares might trade at a discount to net asset value and that any such discount may not be in the interest of shareholders, the Board, in consultation with Eaton Vance, from time to time may review possible actions to reduce any such discount.

On September 30 , 2013, the Board of Trustees of the Fund authorized the continuation of repurchase by the Fund of up to 10% of its then-currently outstanding Common Shares in open-market transactions at a discount to net asset value. The repurchase program has been in effect since August 6, 2012 and does not obligate the Fund to purchase a specific amount of shares. Results of the repurchase program are disclosed in the Fund’s annual and semiannual reports to shareholders.

PREFERRED SHARES

The Fund has no current intention of issuing any shares other than the Common Shares. However, the Declaration of Trust authorizes the issuance of an unlimited number of shares of beneficial interest with preference rights (the “preferred shares”) in one or more series, with rights as determined by the Board, by action of the Board without the approval of the Common Shareholders.

Under the requirements of the 1940 Act, the Fund must, immediately after the issuance of any preferred shares, have an “asset coverage” of at least 200%. Asset coverage means the ratio which the value of the total assets of the Fund, less all liabilities and indebtedness not represented by senior securities (as defined in the 1940 Act), bears to the aggregate amount of senior securities representing indebtedness of the Fund, if any, plus the aggregate liquidation preference of the preferred shares. If the Fund seeks a rating for preferred shares, asset coverage requirements in addition to those set forth in the 1940 Act may be imposed. The liquidation value of any preferred shares would be expected to equal their aggregate original purchase price plus

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redemption premium, if any, together with any accrued and unpaid distributions thereon (on a cumulative basis), whether or not earned or declared. The terms of any preferred shares, including their distribution rate, voting rights, liquidation preference and redemption provisions, will be determined by the Board (subject to applicable law and the Fund’s Declaration of Trust) if and when it authorizes preferred shares. The Fund may issue preferred shares that provide for the periodic redetermination of the distribution rate at relatively short intervals through an auction or remarketing procedure, although the terms of such preferred shares may also enable the Fund to lengthen such intervals. At times, the distribution rate on any preferred shares may exceed the Fund’s return after expenses on the investment of proceeds from the preferred shares and the Fund’s leverage structure, resulting in a lower rate of return to Common Shareholders than if the Fund were not so structured.

In the event of any voluntary or involuntary liquidation, dissolution or winding up of the Fund, the terms of any preferred shares may entitle the holders of preferred shares to receive a preferential liquidating distribution (expected to equal the original purchase price per share plus redemption premium, if any, together with accrued and unpaid dividends, whether or not earned or declared and on a cumulative basis) before any distribution of assets is made to Common Shareholders. After payment of the full amount of the liquidating distribution to which they are entitled, the preferred shareholders would not be entitled to any further participation in any distribution of assets by the Fund.

Holders of preferred shares, voting as a class, would be entitled to elect two of the Fund’s Trustees if any preferred shares are issued. The holders of both the Common Shares and the preferred shares (voting together as a single class with each share entitling its holder to one vote) shall be entitled to elect the remaining Trustees of the Fund. Under the 1940 Act, if at any time dividends on the preferred shares are unpaid in an amount equal to two full years’ dividends thereon, the holders of all outstanding preferred shares, voting as a class, will be allowed to elect a majority of the Board until all distributions in arrears have been paid or declared and set apart for payment. In addition, if required by a Rating Agency rating the preferred shares or if the Board determines it to be in the best interests of the Common Shareholders, issuance of the preferred shares may result in more restrictive provisions than required under the 1940 Act. In this regard, holders of preferred shares may be entitled to elect a majority of the Board in other circumstances, for example, if one payment on the preferred shares is in arrears. The differing rights of the holders of preferred and Common Shares with respect to the election of Trustees do not affect the obligation of all Trustees to take actions they believe to be consistent with the best interests of the Fund. All such actions must be consistent with (i) the obligations of the Fund with respect to the holders of preferred shares (which obligations arise primarily from the contractual terms of the preferred shares, as specified in the Declaration of Trust and By-laws of the Fund) and (ii) the fiduciary duties owed to the Fund, which include the duties of loyalty and care.

In the event of any future issuance of preferred shares, the Fund likely would seek a credit rating for such preferred shares from a Rating Agency. In such event, as long as preferred shares are outstanding, the composition of its portfolio will reflect guidelines established by such Rating Agency. Based on previous guidelines established by Rating Agencies for the securities of other issuers, the Fund anticipates that the guidelines with respect to any preferred shares would establish a set of tests for portfolio composition and asset coverage that supplement (and in some cases are more restrictive than) the applicable requirements under the 1940 Act. Although no assurance can be given as to the nature or extent of the guidelines that may be imposed in connection with obtaining a rating of any preferred shares, the Fund anticipates that such guidelines would include asset coverage requirements that are more restrictive than those under the 1940 Act, restrictions on certain portfolio investments and investment practices and certain mandatory redemption requirements relating to any preferred shares. No assurance can be given that the guidelines actually imposed with respect to any preferred shares by a Rating Agency would be more or less restrictive than those described in this Prospectus.

CREDIT FACILITY/COMMERCIAL PAPER PROGRAM

The Fund has no current intention to borrow money for the purpose of obtaining investment leverage. If, in the future, the Fund determines to engage in investment leverage using borrowings, the Fund may enter into definitive agreements with respect to a credit facility/commercial paper program or other borrowing program, pursuant to which the Fund would expect to be entitled to borrow up to a specified amount. Any such borrowings would constitute financial leverage. Borrowings under such a facility/ commercial paper program would not be expected to be convertible into any other securities of the Fund. Outstanding amounts would be expected to be prepayable by the Fund prior to final maturity without significant penalty, and no sinking fund or mandatory retirement provisions would be expected to apply. Outstanding amounts would be payable at maturity or such earlier times as required by the agreement. The Fund may be required to prepay outstanding amounts under the facility/program or incur a penalty rate of interest in the event of the occurrence of certain events of default. The Fund would be expected to indemnify the lenders under the facility/program against liabilities they may incur in connection with the facility/program.

In addition, the Fund expects that any such credit facility/program would contain covenants that, among other things, likely would limit the Fund’s ability to pay distributions in certain circumstances, incur additional debt, change its fundamental investment policies and engage in certain transactions, including mergers and consolidations, and may require asset coverage ratios in addition to those required by the 1940 Act. The Fund may be required to pledge its assets and to maintain a portion of

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its assets in cash or high-grade securities as a reserve against interest or principal payments and expenses. The Fund expects that any credit facility/program would have customary covenant, negative covenant and default provisions. There can be no assurance that the Fund will enter into an agreement for a credit facility/program on terms and conditions representative of the foregoing, or that additional material terms will not apply. In addition, if entered into, any such credit facility/program may in the future be replaced or refinanced by one or more credit facilities having substantially different terms or by the issuance of preferred shares or debt securities.

EFFECTS OF POSSIBLE FUTURE LEVERAGE

As discussed above, the Fund has no current intention to issue preferred shares or to borrow money for the purpose of obtaining investment leverage. In the event that the Fund determines in the future to utilize investment leverage, there can be no assurance that such a leveraging strategy would be successful during any period in which it is employed. Leverage creates risks for Common Shareholders, including the likelihood of greater volatility of net asset value and market price of the Common Shares and the risk that fluctuations in distribution rates on any preferred shares or fluctuations in borrowing costs may affect the return to Common Shareholders. To the extent that amounts available for distribution derived from securities purchased with the proceeds of leverage exceed the cost of such leverage, the Fund’s distributions would be greater than if leverage had not been used. Conversely, if the amounts available for distribution derived from securities purchased with leverage proceeds are not sufficient to cover the cost of leverage, distributions to Common Shareholders would be less than if leverage had not been used. In the latter case, Eaton Vance, in its best judgment, may nevertheless determine to maintain the Fund’s leveraged position if it deems such action to be appropriate. The costs of an offering of preferred shares and/or a borrowing program would be borne by Common Shareholders and consequently would result in a reduction of the net asset value of Common Shares. See “Risk Considerations -- Financial Leverage Risk.”

In addition, the fee paid to Eaton Vance will be calculated on the basis of the Fund’s average daily gross assets, including proceeds from the issuance of preferred shares and/or borrowings, so the fees would be higher if leverage is utilized. In this regard, holders of preferred shares would not bear the investment advisory fee. Rather, Common Shareholders would bear the portion of the investment advisory fee attributable to the assets purchased with the proceeds of the preferred shares offering. See “Risk Considerations -- Financial Leverage Risk.”

CERTAIN PROVISIONS OF THE DECLARATION OF TRUST

Anti-Takeover Provisions in the Declaration of Trust

The Declaration of Trust includes provisions that could have the effect of limiting the ability of other entities or persons to acquire control of the Fund or to change the composition of its Board and could have the effect of depriving Common Shareholders of an opportunity to sell their Common Shares at a premium over prevailing market prices by discouraging a third party from seeking to obtain control of the Fund. These provisions may have the effect of discouraging attempts to acquire control of the Fund, which attempts could have the effect of increasing the expenses of the Fund and interfering with the normal operation of the Fund. The Board is divided into three classes, with the term of one class expiring at each annual meeting of shareholders. At each annual meeting, one class of Trustees is elected to a three-year term. This provision could delay for up to two years the replacement of a majority of the Board. A Trustee may be removed from office only for cause by a written instrument signed by the remaining Trustees or by a vote of the holders of at least two-thirds of the class of shares of the Fund that elected such Trustee and are entitled to vote on the matter.

In addition, the Declaration of Trust requires the favorable vote of the holders of at least 75% of the outstanding shares of each class of the Fund, voting as a class, then entitled to vote to approve, adopt or authorize certain transactions with 5%-or-greater holders of a class of shares and their associates, unless the Board shall by resolution have approved a memorandum of understanding with such holders, in which case normal voting requirements would be in effect. For purposes of these provisions, a 5%-or-greater holder of a class of shares (a “Principal Shareholder”) refers to any person who, whether directly or indirectly and whether alone or together with its affiliates and associates, beneficially owns 5% or more of the outstanding shares of any class of beneficial interest of the Fund. The transactions subject to these special approval requirements are: (i) the merger or consolidation of the Fund or any subsidiary of the Fund with or into any Principal Shareholder; (ii) the issuance of any securities of the Fund to any Principal Shareholder for cash; (iii) the sale, lease or exchange of all or any substantial part of the assets of the Fund to any Principal Shareholder (except assets having an aggregate fair market value of less than $1,000,000, aggregating for the purpose of such computation all assets sold, leased or exchanged in any series of similar transactions within a twelve-month period); or (iv) the sale, lease or exchange to the Fund or any subsidiary thereof, in exchange for securities of the Fund, of any assets of any Principal Shareholder (except assets having an aggregate fair market value of less than $1,000,000, aggregating for the purposes of such computation all assets sold, leased or exchanged in any series of similar transactions within a twelve-month period).

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

The Board has determined that provisions with respect to the Board and the 75% voting requirements described above, which voting requirements are greater than the minimum requirements under Massachusetts law or the 1940 Act, are in the best interest of Common Shareholders generally. Reference should be made to the Declaration of Trust on file with the SEC for the full text of these provisions.

CONVERSION TO OPEN-END FUND

The Fund may be converted to an open-end management investment company at any time if approved by the lesser of (i) two-thirds or more of the Fund’s then outstanding Common Shares and preferred shares (if any), each voting separately as a class, or (ii) more than 50% of the then outstanding Common Shares and preferred shares (if any), voting separately as a class if such conversion is recommended by at least 75% of the Trustees then in office. If approved in the foregoing manner, conversion of the Fund could not occur until 90 days after the shareholders’ meeting at which such conversion was approved and would also require at least 30 days’ prior notice to all shareholders. Conversion of the Fund to an open-end management investment company also would require the redemption of any outstanding preferred shares and could require the repayment of borrowings, which would eliminate any future leveraged capital structure of the Fund with respect to the Common Shares. In the event of conversion, the Common Shares would cease to be listed on the NYSE or other national securities exchange or market system. The Board believes that the closed-end structure is desirable, given the Fund’s investment objectives and policies. Investors should assume, therefore, that it is unlikely that the Board would vote to convert the Fund to an open-end management investment company. Shareholders of an open-end management investment company may require the company to redeem their shares at any time (except in certain circumstances as authorized by or under the 1940 Act) at their net asset value, less such redemption charge, if any, as might be in effect at the time of a redemption. If the Fund were to convert to an open-end investment company, the Fund expects it would pay all such redemption requests in cash, but would likely reserve the right to pay redemption requests in a combination of cash or securities. If such partial payment in securities were made, investors may incur brokerage costs in converting such securities to cash. If the Fund were converted to an open-end fund, it is likely that new Common Shares would be sold at net asset value plus a sales load.

Custodian and Transfer Agent

State Street Bank and Trust Company (“State Street”), State Street Financial Center, One Lincoln Street, Boston, MA 02111, is the custodian of the Fund and will maintain custody of the securities and cash of the Fund. State Street maintains the Fund’s general ledger and computes net asset value per share at least weekly. State Street also attends to details in connection with the sale, exchange, substitution, transfer and other dealings with the Fund’s investments, and receives and disburses all funds. State Street also assists in preparation of shareholder reports and the electronic filing of such reports with the SEC.

American Stock Transfer & Trust Company, LLC, 6201 15^th Avenue, Brooklyn, NY 11219 is the transfer agent and dividend disbursing agent of the Fund.

Legal Opinions

Certain legal matters in connection with the Common Shares will be passed upon for the Fund by internal counsel for Eaton Vance.

Reports to Shareholders

The Fund will send to Common Shareholders unaudited semi-annual and audited annual reports, including a list of investments held.

Independent Registered Public Accounting Firm

Deloitte & Touche LLP, 200 Berkeley Street, Boston, MA 02116, independent registered public accounting firm, audits the Fund’s financial statements and provides other audit, tax and related services.

Additional Information

The Prospectus and the Statement of Additional Information do not contain all of the information set forth in the Registration Statement that the Fund has filed with the SEC. The complete Registration Statement may be obtained from the SEC upon payment of the fee prescribed by its rules and regulations. The Statement of Additional Information can be obtained without charge by calling 1-800-262-1122.

Statements contained in this Prospectus as to the contents of any contract or other documents referred to are not necessarily complete, and, in each instance, reference is made to the copy of such contract or other document filed as an exhibit to the Registration Statement of which this Prospectus forms a part, each such statement being qualified in all respects by such reference.

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Table of Contents for the Statement of Additional Information


	Page
Additional Investment Information and Restrictions	2
Trustees and Officers	8
Investment Advisory and Other Services	17
Determination of Net Asset Value	22
Portfolio Trading	23
Taxes	25
Other Information	30
Custodian	31
Independent Registered Public Accounting Firm	31
Financial Statements	31
APPENDIX A: Eaton Vance Funds Proxy Voting Policy and Procedures	32
APPENDIX B: Adviser Proxy Voting Policies and Procedures	34
APPENDIX C: Parametric Portfolio Associates LLC Proxy Voting Policies and Procedures	39

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

The Fund’s Privacy Policy

The Eaton Vance organization is committed to ensuring your financial privacy. Each of the financial institutions identified below has in effect the following policy (“Privacy Policy”) with respect to nonpublic personal information about its customers:

Only such information received from you, through application forms or otherwise, and information about your Eaton Vance fund transactions will be collected. This may include information such as name, address, social security number, tax status, account balances and transactions.

None of such information about you (or former customers) will be disclosed to anyone, except as permitted by law (which includes disclosure to employees necessary to service your account). In the normal course of servicing a customer’s account, Eaton Vance may share information with unaffiliated third parties that perform various required services such as transfer agents, custodians and broker/dealers.

Policies and procedures (including physical, electronic and procedural safeguards) are in place that are designed to protect the confidentiality of such information.

We reserve the right to change our Privacy Policy at any time upon proper notification to you. Customers may want to review our Privacy Policy periodically for changes by accessing the link on our homepage: www.eatonvance.com.

Our pledge of privacy applies to the following entities within the Eaton Vance organization: the Eaton Vance Family of Funds, Eaton Vance Management, Eaton Vance Investment Counsel, Eaton Vance Distributors, Inc., Eaton Vance Trust Company, Eaton Vance Management (International) Limited, Eaton Vance Management’s Real Estate Investment Group and Boston Management and Research.

In addition, our Privacy Policy applies only to those Eaton Vance customers who are individuals and who have a direct relationship with us. If a customer’s account (i.e., fund shares) is held in the name of a third-party financial adviser/broker-dealer, it is likely that only such adviser’s privacy policies apply to the customer. This notice supersedes all previously issued privacy disclosures.

For more information about Eaton Vance’s Privacy Policy, please call 1-800-262-1122 .

Eaton Vance Tax-Managed Buy-Write Income Fund

Prospectus dated April ___, 2017

Up to 2,965,949 Shares

Eaton Vance Tax-Managed Buy-Write Income Fund

Common Shares

Prospectus April ___, 2017

ETBSUPPLEMENT


PRELIMINARY PROSPECTUS	SUBJECT TO COMPLETION	[_____], 2017

(EATON VANCE LOGO)

Prospectus Supplement

(To Prospectus dated [_____], 2017)

Eaton Vance Tax-Managed Buy-Write Income Fund

Up to [_____] Common Shares

Eaton Vance Tax-Managed Buy-Write Income Fund (the “Fund,” “we,” or “our”) is a diversified, closed-end management investment company, which commenced operations on April 29, 2005. Our primary investment objective is to provide current income and gains, with a secondary objective of capital appreciation.

The Fund has entered into a distribution agreement dated [_____], 2017 (the “Distribution Agreement”) with [_____] (the “Distributor”) relating to the Common Shares offered by this Prospectus Supplement and the accompanying Prospectus dated [_____], 2017. The Distributor has entered into a dealer agreement, dated [_____], 2017, (the “Dealer Agreement”) with [_____] (the “Dealer”) with respect to the Fund relating to the Common Shares offered by this Prospectus Supplement and the accompanying Prospectus. In accordance with the terms of the Dealer Agreement, we may offer and sell our Common Shares, $0.01 par value per share, from time to time through the Dealer as sub-placement agent for the offer and sale of the Common Shares. Under the Investment Company Act of 1940, as amended (the “1940 Act”), the Fund may not sell any Common Shares at a price below the current net asset value of such Common Shares, exclusive of any distributing commission or discount.

Our Common Shares are listed on the New York Stock Exchange (“NYSE”) under the symbol “ETB.” As of [_____], 2017, the last reported sale price for our Common Shares on the NYSE was $[_____] per share.

The Fund will compensate the Distributor with respect to sales of the Common Shares at a commission rate of 1% of the gross proceeds of the sale of Common Shares. The Distributor will compensate the Dealer out of this commission at a certain percentage rate of the gross proceeds of the sale of Common Shares sold under the Dealer Agreement, with the exact amount of such compensation to be mutually agreed upon by the Distributor and the Dealer from time to time. In connection with the sale of the Common Shares on the Fund’s behalf, the Distributor may be deemed to be an “underwriter” within the meaning of the 1933 Act and the compensation of the Dealer may be deemed to be underwriting commissions or discounts.

The Common Shares have traded both at a premium and a discount to net asset value (“NAV”). The Fund cannot predict whether Common Shares will trade in the future at a premium or discount to NAV. The provisions of the 1940 Act, generally require that the public offering price of common shares (less any underwriting commissions and discounts) must equal or exceed the NAV per share of a company’s common stock (calculated within 48 hours of pricing). The Fund’s issuance of Common Shares may have an adverse effect on prices in the secondary market for the Fund’s Common Shares by increasing the number of Common Shares available, which may put downward pressure on the market price for the Fund’s Common Shares. Shares of common stock of closed-end investment companies frequently trade at a discount from NAV, which may increase investors’ risk of loss.

Investing in our securities involves certain risks. You could lose some or all of your investment. See “Investment Objectives, Policies and Risks” beginning on page 18 of the accompanying Prospectus. You should consider carefully these risks together with all of the other information contained in this Prospectus Supplement and the accompanying Prospectus before making a decision to purchase our securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this Prospectus Supplement or the accompanying Prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

Prospectus Supplement dated [_____], 2017

This Prospectus Supplement, together with the accompanying Prospectus, sets forth concisely the information about the Fund that you should know before investing. You should read this Prospectus Supplement and the accompanying Prospectus, which contain important information, before deciding whether to invest in our securities. You should retain the accompanying Prospectus and this Prospectus Supplement for future reference. A Statement of Additional Information, dated [_____], 2017 as supplemented from time to time, containing additional information about the Fund, has been filed with the Securities and Exchange Commission (the “SEC”) and is incorporated by reference in its entirety into this Prospectus Supplement and the accompanying Prospectus. This Prospectus Supplement, the accompanying Prospectus and the Statement of Additional Information are part of a “shelf” registration statement that we filed with the SEC. This Prospectus Supplement describes the specific details regarding this offering, including the method of distribution. If information in this Prospectus Supplement is inconsistent with the accompanying Prospectus or the Statement of Additional Information, you should rely on this Prospectus Supplement. You may request a free copy of the Statement of Additional Information, the table of contents of which is on

page 42 of the accompanying Prospectus, request a free copy of our annual and semi-annual reports, request other information or make shareholder inquiries, by calling toll-free 1-800-262-1122 or by writing to the Fund at Two International Place, Boston, Massachusetts 02110. The Fund’s annual and semi-annual reports also are available on our website at http://www.eatonvance.com and on the SEC’s website, as described below, where the Fund’s Statement of Additional Information can be obtained. Information included on our website does not form part of this Prospectus Supplement or the accompanying Prospectus. You can review and copy documents we have filed at the SEC’s Public Reference Room in Washington, D.C. Call 1-202-551-8090 for information. The SEC charges a fee for copies. You can get the same information free from the SEC’s website (http://www.sec.gov). You may also e-mail requests for these documents to publicinfo@sec.gov or make a request in writing to the SEC’s Public Reference Section, Washington, D.C. 20549-0102.

Our securities do not represent a deposit or obligation of, and are not guaranteed or endorsed by, any bank or other insured depository institution and are not federally insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board or any other government agency.

TABLE OF CONTENTS

You should rely only on the information contained in, or incorporated by reference into, this Prospectus Supplement and the accompanying Prospectus in making your investment decisions. The Fund has not authorized any person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. The Fund is not making an offer to sell the securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information in this Prospectus Supplement and the accompanying Prospectus is accurate only as of the dates on their covers. The Fund’s business, financial condition and prospects may have changed since the date of its description in this Prospectus Supplement or the date of its description in the accompanying Prospectus.


Prospectus Supplement

Prospectus Supplement Summary	1
Capitalization	2
Summary of Fund Expenses	3
Market and Net Asset Value Information	4
Use of Proceeds	5
Plan of Distribution	6
Legal Matters	6
Available Information	7

Prospectus

Prospectus Summary	5
Summary of Fund Expenses	15
Financial Highlights and Investment Performance	16
The Fund	18
Use of Proceeds	18
Investment Objectives, Policies and Risks	18
Management of the Fund	30
Plan of Distribution	32
Distributions	33
Federal Income Tax Matters	34
Dividend Reinvestment Plan	37
Description of Capital Structure	37
Custodian and Transfer Agent	41
Legal Opinions	41
Reports to Shareholders	41
Independent Registered Public Accounting Firm	41
Additional Information	41
Table of Contents for the Statement of Additional Information	42
The Fund’s Privacy Policy	43

Until [_____], 2017 (25 days after the date of this Prospectus Supplement), all dealers that buy, sell or trade the Common Shares, whether or not participating in this offering, may be required to deliver the Prospectus and this Prospectus Supplement. This requirement is in addition to the dealers’ obligation to deliver the Prospectus and this Prospectus Supplement when acting as underwriters and with respect to their unsold allotments or subscriptions.

iii

CAUTIONARY NOTICE REGARDING FORWARD-LOOKING STATEMENTS

This Prospectus Supplement, the accompanying Prospectus and the Statement of Additional Information contain “forward-looking statements.” Forward-looking statements can be identified by the words “may,” “will,” “intend,” “expect,” “estimate,” “continue,” “plan,” “anticipate,” and similar terms and the negative of such terms. Such forward-looking statements may be contained in this Prospectus Supplement as well as in the accompanying Prospectus. By their nature, all forward-looking statements involve risks and uncertainties, and actual results could differ materially from those contemplated by the forward-looking statements. Several factors that could materially affect our actual results are the performance of the portfolio of securities we hold, the price at which our shares will trade in the public markets and other factors discussed in our periodic filings with the SEC.

Although we believe that the expectations expressed in our forward-looking statements are reasonable, actual results could differ materially from those projected or assumed in our forward-looking statements. Our future financial condition and results of operations, as well as any forward-looking statements, are subject to change and are subject to inherent risks and uncertainties, such as those disclosed in the “Investment Objectives, Policies and Risks” section of the accompanying Prospectus. All forward-looking statements contained or incorporated by reference in this Prospectus Supplement or the accompanying Prospectus are made as of the date of this Prospectus Supplement or the accompanying Prospectus, as the case may be. Except for our ongoing obligations under the federal securities laws, we do not intend, and we undertake no obligation, to update any forward-looking statement. The forward-looking statements contained in this Prospectus Supplement, the accompanying Prospectus and the Statement of Additional Information are excluded from the safe harbor protection provided by section 27A of the 1933 Act.

Currently known risk factors that could cause actual results to differ materially from our expectations include, but are not limited to, the factors described in the “Investment Objectives, Policies and Risks” section of the accompanying Prospectus. We urge you to review carefully that section for a more detailed discussion of the risks of an investment in our securities.

Prospectus Supplement Summary

The following summary is qualified in its entirety by reference to the more detailed information included elsewhere in this Prospectus Supplement and in the accompanying Prospectus and in the Statement of Additional Information.

THE FUND

THE ADVISER

Eaton Vance acts as the Fund’s investment adviser under an Investment Advisory Agreement (the “Advisory Agreement”). The Adviser’s principal office is located at Two International Place, Boston, MA 02110. Eaton Vance, its affiliates and predecessor companies have been managing assets of individuals and institutions since 1924 and of investment companies since 1931. As of January 31, 2017, Eaton Vance and its affiliates managed approximately $363.7 billion of fund and separate account assets on behalf of clients, including approximately $99.6 billion in equity assets. Eaton Vance has engaged its affiliate Parametric Portfolio Associates LLC (“Parametric” or the “Sub-Adviser”) as the sub-adviser to the Fund. Parametric managed approximately $185.9 billion in assets as of January 31, 2017. Eaton Vance is a wholly-owned subsidiary of Eaton Vance Corp., a publicly-held holding company, which through its subsidiaries and affiliates engages primarily in investment management, administration and marketing activities.

Under the general supervision of the Fund’s Board, the Adviser will carry out the investment and reinvestment of the assets of the Fund, will furnish continuously an investment program with respect to the Fund, will determine which securities should be purchased, sold or exchanged, and will implement such determinations. The Adviser will furnish to the Fund investment advice and office facilities, equipment and personnel for servicing the investments of the Fund. The Adviser will compensate all Fundees and officers of the Fund who are members of the Adviser’s organization and who render investment services to the Fund, and will also compensate all other Adviser personnel who provide research and investment services to the Fund. In return for these services, facilities and payments, the Fund has agreed to pay the Adviser as compensation under the Advisory Agreement a fee in the amount of 1.00% of the average daily gross assets of the Fund. Gross assets of the Fund shall be calculated by deducting accrued liabilities of the Fund not including the amount of any preferred shares outstanding or the principal amount of any indebtedness for money borrowed. During periods in which the Fund is using leverage, the fees paid to Eaton Vance for investment advisory services will be higher than if the Fund did not use leverage because the fees paid will be calculated on the basis of the Fund’s gross assets, including proceeds from any borrowings and from the issuance of preferred shares. Under the Sub-Advisory Agreement between Eaton Vance and Parametric, Eaton Vance (and not the Fund) pays Parametric a portion of the advisory fee for sub-advisory services provided to the Fund.

THE OFFERING

The Fund has entered into a distribution agreement dated [_____], 2017 (the “Distribution Agreement”) with [_____] (the “Distributor”) relating to the Common Shares of beneficial interest (the “Common Shares”), offered by this Prospectus Supplement and the accompanying Prospectus dated [_____], 2017 (the “Offering”). The Distributor has entered into a dealer agreement dated [_____], 2017 (the “Dealer Agreement”) with [_____] (the “Dealer”) with respect to the Fund relating to the Common Shares offered by this Prospectus Supplement and the accompanying Prospectus. In accordance with the terms of the Dealer Agreement, the Fund may offer and sell up to [_____] Common Shares, par value $0.01 per Common Share, from time to time through the Dealer as sub-placement agent for the offer and sale of the Common Shares.

S-1

Offerings of the Common Shares will be subject to the provisions of the 1940 Act, which generally require that the public offering price of common shares of a closed-end investment company (exclusive of distribution commissions and discounts) must equal or exceed the net asset value per share of the company’s common shares (calculated within 48 hours of pricing), absent shareholder approval or under certain other circumstances.

Sales of the Common Shares, if any, under this Prospectus Supplement and the accompanying Prospectus may be made in negotiated transactions or transactions that are deemed to be “at the market” as defined in Rule 415 under the 1933 Act, including sales made directly on the New York Stock Exchange (“NYSE”) or sales made to or through a market maker other than on an exchange. The Common Shares may not be sold through agents, underwriters or dealers without delivery or deemed delivery of a Prospectus and an accompanying Prospectus Supplement describing the method and terms of the offering of Common Shares.

LISTING AND SYMBOL

The Fund’s currently outstanding Common Shares are listed on the NYSE under the symbol “ETB.” Any new Common Shares offered and sold hereby are expected to be listed on the NYSE and trade under this symbol. The net asset value of the Common Shares on [_____], 2017 was $[_____] per share. As of [_____], 2017, the last reported sale price for the Common Shares was $[_____].

USE OF PROCEEDS

The Fund currently intends to invest substantially all of the net proceeds of any sales of Common Shares pursuant to this Prospectus Supplement in accordance with its investment objectives and policies as described in the accompanying Prospectus under “Investment Objectives, Policies and Risks” within three months of receipt of such proceeds. Such investments may be delayed up to three months if suitable investments are unavailable at the time or for other reasons, such as market volatility and lack of liquidity in the markets of suitable investments. Pending such investment, the Fund anticipates that it will invest the proceeds in short-term money market instruments, securities with remaining maturities of less than one year, cash or cash equivalents. A delay in the anticipated use of proceeds could lower returns and reduce the Fund’s distribution to the holders of Common Shares (“Common Shareholders”) or result in a distribution consisting principally of a return of capital.

Capitalization

We may offer and sell up to [_____] of our Common Shares, $0.01 par value per share, from time to time through the Dealer as sub-placement agent under this Prospectus Supplement and the accompanying Prospectus. There is no guarantee that there will be any sales of our Common Shares pursuant to this Prospectus Supplement and the accompanying Prospectus. The table below assumes that we will sell [_____] Common Shares at a price of $[_____] per share (the last reported sale price per share of our Common Shares on the NYSE on [_____], 2017). Actual sales, if any, of our Common Shares under this Prospectus Supplement and the accompanying Prospectus may be greater or less than $[_____] per share, depending on the market price of our Common Shares at the time of any such sale. To the extent that the market price per share of our Common Shares on any given day is less than the net asset value per share on such day, we will instruct the Dealer not to make any sales on such day.

S-2

The following table sets forth our capitalization:

• on a historical basis as of December 31, 2016 (audited); and

• on a pro forma as adjusted basis to reflect the assumed sale of [_____] Common Shares at $[_____] per share (the last reported sale price for our Common Shares on the NYSE on [_____], 2017), in an offering under this Prospectus Supplement and the accompanying Prospectus, after deducting the assumed commission of $[_____] (representing an estimated commission to the Distributor of 1% of the gross proceeds of the sale of Common Shares, of which a certain percentage will be paid to the Dealer in connection with sales of Common Shares effected in this offering).


	As of December 31, 2016 (audited)	Pro Forma (unaudited)
	Actual	As adjusted
Net Assets	[_____]	[_____]
Common shares outstanding, $0.01 par value per share	[_____]	[_____]
Paid-in capital	[_____]	[_____]
Undistributed net investment income	[_____]	[_____]
Accumulated net realized loss on investments, futures contracts and foreign currency transactions	[_____]	[_____]
Net unrealized appreciation (depreciation) on investments, futures contracts and swap contracts	[_____]	[_____]
Net Assets	[_____]	[_____]
Net asset value per share	[_____]	[_____]

Summary of Fund Expenses

The purpose of the table below is to help you understand all fees and expenses that you, as a Common Shareholder, would bear directly or indirectly. The table reflects the issuance of preferred shares in an amount equal to [_____]% of the Fund’s total assets and borrowings in an amount equal to [_____]% of the Fund’s total assets (including the proceeds of all such leverage) and shows Fund expenses as a percentage of net assets attributable to Common Shares⁽¹⁾ for the year ended December 31, 2016.


Common Shareholder transaction expenses
Sales load paid by you (as a percentage of offering price)	1%⁽¹⁾
Offering expenses (as a percentage of offering price)	None⁽²⁾
Dividend reinvestment plan fees	None⁽³⁾
Annual expenses	Percentage of net assets attributable to Common Shares⁽⁴⁾
Investment advisory fee	[_____]%
Other expenses	[_____]%
Total annual Fund operating expenses	[_____]%

S-3

EXAMPLE

The following example illustrates the expenses that Common Shareholders would pay on a $1,000 investment in Common Shares, assuming (i) total annual expenses of [_____]% of net assets attributable to Common Shares in years 1 through 10; (ii) a sales load of 1.00%; (Iii) a 5% annual return; and (iv) all distributions are reinvested at NAV:


1 Year	3 Years	5 Years	10 Years
$[_____]	$[_____]	$[_____]	$[_____]

The above table and example and the assumption in the example of a 5% annual return are required by regulations of the SEC that are applicable to all investment companies; the assumed 5% annual return is not a prediction of, and does not represent, the projected or actual performance of the Fund’s Common Shares. For more complete descriptions of certain of the Fund’s costs and expenses, see “Management of the Fund.” In addition, while the example assumes reinvestment of all dividends and distributions at NAV, participants in the Fund’s dividend reinvestment plan may receive Common Shares purchased or issued at a price or value different from NAV. See “Distributions” and “Dividend Reinvestment Plan.” The example does not include estimated offering costs, which would cause the expenses shown in the example to increase.

___________________

⁽¹⁾

If Common Shares are sold to or through underwriters, the Prospectus Supplement will set forth any applicable sales load.

⁽²⁾

⁽³⁾

You will be charged a $5.00 service charge and pay brokerage charges if you direct the plan agent to sell your Common Shares held in a dividend reinvestment account.

Market and Net Asset Value Information

Our Common Shares are listed on the NYSE under the symbol “ETB.” Our Common Shares commenced trading on the NYSE in 2005.

Our Common Shares have traded both at a premium and a discount to net asset value or NAV. We cannot predict whether our shares will trade in the future at a premium or discount to NAV. The provisions of the 1940 Act generally require that the public offering price of Common Shares (less any underwriting commissions and discounts) must equal or exceed the NAV per share of a company’s common stock (calculated within 48 hours of pricing). Our issuance of Common Shares may have an adverse effect on prices in the secondary market for our Common Shares by increasing the number of Common Shares available, which may put downward pressure on the market price for our Common Shares. Shares of Common Stock of closed-end investment companies frequently trade at a discount from NAV. See “Prospectus Summary—Special Risk Considerations—Discount from or premium to NAV” on page 10 of the accompanying Prospectus.

S-4

The following table sets forth for the period indicated the high and low closing market prices for Common Shares on the NYSE, and the corresponding NAV per share and the premium or discount to NAV per share at which the Fund’s Common Shares were trading as of the same date. NAV is determined no less frequently than daily, generally on each day of the week that the NYSE is open for trading. See “Determination of net asset value” on page 22 of the accompanying Statement of Additional Information for information as to the determination of the Fund’s net asset value.


	Market Price		NAV per Share on Date of Market Price High and Low		NAV Premium/(Discount) on Date of Market Price High and Low
Fiscal Quarter Ended	High	Low	High	Low	High	Low
[_____], 2017	[_____]	[_____]	[_____]	[_____]	[_____]%	[_____]%

The last reported sale price, NAV per Common Share and percentage premium/(discount) to NAV per Common Share on [_____], 2017, were $[_____], $[_____] and [_____]%, respectively. As of [_____], 2017, we had [_____] Common Shares outstanding and net assets of approximately $[_____].

The following table provides information about our outstanding Common Shares as of [_____], 2017:


Title of Class	Amount Authorized	Amount Held by the Fund or for its Account	Amount Outstanding
Common Shares	Unlimited	[_____]	[_____]

Use of Proceeds

Sales of our Common Shares, if any, under this Prospectus Supplement and the accompanying Prospectus may be made in negotiated transactions or transactions that are deemed to be “at the market” as defined in Rule 415 under the 1933 Act, including sales made directly on the NYSE or sales made to or through a market maker other than on an exchange. There is no guarantee that there will be any sales of our Common Shares pursuant to this Prospectus Supplement and the accompanying Prospectus. Actual sales, if any, of our Common Shares under this Prospectus Supplement and the accompanying Prospectus may be less than as set forth below in this paragraph. In addition, the price per share of any such sale may be greater or less than the price set forth in this paragraph, depending on the market price of our Common Shares at the time of any such sale. As a result, the actual net proceeds we receive may be more or less than the amount of net proceeds estimated in this Prospectus Supplement. Assuming the sale of all of the Common Shares offered under this Prospectus Supplement and the accompanying Prospectus, at the last reported sale price of $[_____] per share for our Common Shares on the NYSE as of [_____], 2017, we estimate that the net proceeds of this offering will be approximately $[_____] after deducting the estimated sales load and the estimated offering expenses payable by the Fund.

Subject to the remainder of this section, the Fund currently intends to invest substantially all of the net proceeds of any sales of Common Shares pursuant to this Prospectus Supplement in accordance with its investment objectives and policies as described in the accompanying Prospectus under “Investment Objectives, Policies and Risks” within three months of receipt of such proceeds. Such investments may be delayed up to three months if suitable investments are unavailable at the time or for other reasons, such as market volatility and lack of liquidity in the markets of suitable investments. Pending such investment, the Fund anticipates that it will invest the proceeds in short-term money market instruments, securities with remaining maturities of less than one year, cash or cash equivalents. A delay in the anticipated use of proceeds could lower returns and reduce the Fund’s distribution to Common Shareholders or result in a distribution consisting principally of a return of capital.

S-5

Plan of Distribution

Under the Dealer Agreement between the Distributor and the Dealer, upon written instructions from the Distributor, the Dealer will use its reasonable best efforts, to sell, as sub-placement agent, the Common Shares under the terms and subject to the conditions set forth in the Dealer Agreement. The Dealer’s solicitation will continue until the Distributor instructs the Dealer to suspend the solicitations and offers. The Distributor will instruct the Dealer as to the amount of Common Shares to be sold by the Dealer. The Distributor may instruct the Dealer not to sell Common Shares if the sales cannot be effected at or above the price designated by the Distributor in any instruction. To the extent that the market price per share of the Fund’s Common Shares on any given day is less than the net asset value per share on such day, the Distributor will instruct the Dealer not to make any sales on such day. The Distributor or the Dealer may suspend the offering of Common Shares upon proper notice and subject to other conditions.

The Dealer will provide written confirmation to the Distributor following the close of trading on the day on which Common Shares are sold under the Dealer Agreement. Each confirmation will include the number of shares sold on the preceding day, the net proceeds to the Fund and the compensation payable by the Distributor to the Dealer in connection with the sales.

The Fund will compensate the Distributor with respect to sales of the Common Shares at a commission rate of 1.00% of the gross proceeds of the sale of Common Shares. The Distributor will compensate the Dealer for its services in acting as sub-placement agent in the sale of Common Shares out of this commission at a certain percentage rate of the gross proceeds of the sale of Common Shares sold under the Dealer Agreement, with the exact amount of such compensation to be mutually agreed upon by the Distributor and the Dealer from time to time. There is no guarantee that there will be any sales of the Common Shares pursuant to this Prospectus Supplement and the accompanying Prospectus. Actual sales, if any, of the Common Shares under this Prospectus Supplement and the accompanying Prospectus may be greater or less than the price set forth in this paragraph, depending on the market price of Common Shares at the time of any such sale. Eaton Vance will pay the expenses of the Offering (other than the applicable commissions).

Settlement for sales of Common Shares will occur on the third trading day following the date on which such sales are made, in return for payment of the net proceeds to the Fund. There is no arrangement for funds to be received in an escrow, Fund or similar arrangement.

The Distributor has agreed to provide indemnification and contribution to the Dealer against certain civil liabilities, including liabilities under the 1933 Act.

The Dealer Agreement will remain in full force and effect unless terminated by either party upon 30 days’ written notice to the other party.

The principal business address of the Dealer is 1285 Avenue of the Americas, New York, NY 10019.

The Dealer and its affiliates hold or may hold in the future, directly or indirectly, investment interests in the Distributor and its funds. The interests held by the Dealer or its affiliates are not attributable to, and no investment discretion is held by, the Dealer or its affiliates.

Legal Matters

Certain legal matters in connection with the Common Shares will be passed upon for the Fund by internal counsel for Eaton Vance.

S-6

Available Information

We are subject to the informational requirements of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and the 1940 Act and are required to file reports, including annual and semi-annual reports, proxy statements and other information with the SEC. These documents are available on the SEC’s EDGAR system and can be inspected and copied for a fee at the SEC’s public reference room, 100 F Street, N.E., Room 1580, Washington, D.C. 20549. Additional information about the operation of the public reference room facilities may be obtained by calling the SEC at 1-202-551-5850.

This Prospectus Supplement, the accompanying Prospectus and the Statement of Additional Information do not contain all of the information in our registration statement, including amendments, exhibits, and schedules that the Fund has filed with the SEC (file No. 333-214544). Statements in this Prospectus Supplement and the accompanying Prospectus about the contents of any contract or other document are not necessarily complete and in each instance reference is made to the copy of the contract or other document filed as an exhibit to the registration statement, each such statement being qualified in all respects by this reference.

Additional information about us can be found in our registration statement (including amendments, exhibits, and schedules) on Form N-2 filed with the SEC. The SEC maintains a web site (http://www.sec.gov) that contains our registration statement, other documents incorporated by reference, and other information we have filed electronically with the SEC, including proxy statements and reports filed under the Exchange Act.

S-7

ETBSAI


SUBJECT TO COMPLETION		April ___, 2017

STATEMENT OF ADDITIONAL
INFORMATION
April ___, 2017

EATON VANCE TAX-MANAGED BUY-WRITE INCOME FUND

Two International Place

Boston, MA 02110

1-800-262-1122

Table of Contents


	Page
Additional Investment Information and Restrictions	2
Trustees and Officers	8
Investment Advisory and Other Services	17
Determination of Net Asset Value	22
Portfolio Trading	23
Taxes	25
Other Information	30
Custodian	31
Independent Registered Public Accounting Firm	31
Financial Statements	31
APPENDIX A: Eaton Vance Funds Proxy Voting Policy and Procedures	32
APPENDIX B: Adviser Proxy Voting Policies and Procedures	34
APPENDIX C: Parametric Portfolio Associates LLC Proxy Voting Policies and Procedures	39

THE INFORMATION IN THIS STATEMENT OF ADDITIONAL INFORMATION (“SAI”) IS NOT COMPLETE AND MAY BE CHANGED. THESE SECURITIES MAY NOT BE SOLD UNTIL THE REGISTRATION STATEMENT FILED WITH THE SECURITIES AND EXCHANGE COMMISSION IS EFFECTIVE. THIS SAI, WHICH IS NOT A PROSPECTUS, IS NOT AN OFFER TO SELL THESE SECURITIES AND IS NOT SOLICITING AN OFFER TO BUY THESE SECURITIES IN ANY STATE WHERE THE OFFER OR SALE IS NOT PERMITTED.

THIS STATEMENT OF ADDITIONAL INFORMATION (“SAI”) IS NOT A PROSPECTUS AND IS AUTHORIZED FOR DISTRIBUTION TO PROSPECTIVE INVESTORS ONLY IF PRECEDED OR ACCOMPANIED BY THE PROSPECTUS OF EATON VANCE TAX-MANAGED BUY-WRITE INCOME FUND (THE “FUND”) DATED APRIL ___, 2017 (THE “PROSPECTUS”), AS SUPPLEMENTED FROM TIME TO TIME, WHICH IS INCORPORATED HEREIN BY REFERENCE. THIS SAI SHOULD BE READ IN CONJUNCTION WITH SUCH PROSPECTUS, A COPY OF WHICH MAY BE OBTAINED WITHOUT CHARGE BY CONTACTING YOUR FINANCIAL INTERMEDIARY OR CALLING THE FUND AT 1-800-262-1122.

Capitalized terms used in this SAI and not otherwise defined have the meanings given them in the Fund’s Prospectus and any related Prospectus Supplements.

ADDITIONAL INVESTMENT INFORMATION AND RESTRICTIONS

Primary investment strategies are described in the Prospectus. The following is a description of the various investment policies that may be engaged in, whether as a primary or secondary strategy, and a summary of certain attendant risks. The Adviser and the Sub-Adviser may not buy any of the following instruments or use any of the following techniques unless they believe that doing so will help to achieve the Fund’s investment objectives.

Equity Investments

As described in the Prospectus, the Fund invests primarily in common stocks.

Preferred Stocks

The Fund may invest in preferred stocks of both domestic and foreign issuers. Under normal market conditions, the Fund expects, with respect to that portion of its total assets invested in preferred stocks, to invest only in preferred stocks of investment grade quality as determined by S&P, Fitch or Moody’s or, if unrated, determined to be of comparable quality by Eaton Vance. The foregoing credit quality policies apply only at the time a security is purchased, and the Fund is not required to dispose of a security in the event of a downgrade of an assessment of credit quality or the withdrawal of a rating.

Preferred stock represents an equity interest in a corporation, company or trust that has a higher claim on the assets and earnings than common stock. Preferred stock usually has limited voting rights. Preferred stock involves credit risk, which is the risk that a preferred stock will decline in price, or fail to pay dividends when expected, because the issuer experiences a decline in its financial status. A company’s preferred stock generally pays dividends after the company makes the required payments to holders of its bonds and other debt instruments but before dividend payments are made to common stockholders. However, preferred stock may not pay scheduled dividends or dividend payments may be in arrears. The value of preferred stock may react more strongly than bonds and other debt instruments to actual or perceived changes in the company’s financial condition or prospects. Certain preferred stocks may be convertible to common stock. Preferred stock may be subject to redemption at the option of the issuer at a predetermined price. Because they may make regular income payments, preferred stocks may be considered fixed-income securities for purposes of a Fund’s investment restrictions. In addition to credit risk, investment in preferred stocks involves certain other risks as more fully described in the Prospectus.

Derivative Instruments

Generally, derivatives can be characterized as financial instruments whose performance is derived at least in part from the performance of an underlying reference instrument. Derivative instruments may be acquired in the United States or abroad and include the various types of exchange-traded and over-the-counter (“OTC”) instruments described herein and other instruments with substantially similar characteristics and risks. Derivative instruments may be based on securities, indices, currencies, commodities, economic indicators and events (referred to as “reference instruments”). Fund obligations created pursuant to derivative instruments may be subject to the requirements described under “Asset Coverage” herein.

In addition to writing index call options, the risks of which are described in the Prospectus, the Fund may invest up to 20% of its total assets in other derivative instruments acquired for hedging, risk management and investment purposes (to gain exposure to securities, securities markets, markets indices and/or currencies consistent with the Fund’s investment objectives and policies), provided that no more than 10% of the Fund’s total assets may be invested in such derivative instruments acquired for non-hedging purposes. In the course of pursuing these investment strategies, the Fund may: purchase and sell exchange-listed and over-the-counter put and call options on securities, equity and fixed-income indices and other instruments; purchase and sell futures contracts and options thereon; and enter into various transactions such as swaps, caps, floors or collars. In addition, derivatives may include new techniques, instruments or strategies that are permitted as regulatory changes occur. Foreign exchange traded futures contracts and options thereon may be used only if the Adviser determines that trading on such foreign exchange does not entail risks, including credit and liquidity risks, that are materially greater than the risks associated with trading on CFTC-regulated exchanges.

Derivative instruments are subject to a number of risks, including adverse or unexpected movements in the price of the reference instrument, and counterparty, liquidity, tax, correlation and leverage risks. Use of derivative instruments may cause the realization of higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if such instruments had not been used. Success in using derivative instruments to hedge portfolio assets depends on the degree of price correlation between the derivative instruments and the hedged asset. Imperfect correlation may be caused by several factors, including temporary price disparities among the trading markets for the derivative instrument, the reference instrument and the Fund’s assets. To the extent that a derivative instrument is intended to hedge against an event that does not occur, the Fund may realize losses. Derivatives permit the Fund to increase or decrease the level of risk, or change the character of the risk, to which its

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portfolio is exposed in much the same way as the Fund can increase or decrease the level of risk, or change the character of the risk, of its portfolio by making investments in specific securities. There can be no assurance that the use of derivative instruments will benefit the Fund.

Options. An option contract is a contract that gives the holder of the option, in return for a premium, the right to buy from (in the case of a call) or sell to (in the case of a put) the writer of the option the reference instrument underlying the option (or the cash value of the index) at a specified exercise price at any time during the term of the option. The writer of an option on a security has the obligation upon exercise of the option to deliver the reference instrument (or the cash) upon payment of the exercise price or to pay the exercise price upon delivery of the reference instrument (or the cash). Upon exercise of an index option, the writer of an option on an index is obligated to pay the difference between the cash value of the index and the exercise price multiplied by the specified multiplier for the index option. Options may be “covered,” meaning that the party required to deliver the reference instrument if the option is exercised owns that instrument (or has set aside sufficient assets to meet its obligation to deliver the instrument). Options may be listed on an exchange or traded in the OTC market. In general, exchange-traded options have standardized exercise prices and expiration dates and may require the parties to post margin against their obligations, and the performance of the parties’ obligations in connection with such options is guaranteed by the exchange or a related clearing corporation. OTC options have more flexible terms negotiated between the buyer and the seller, but generally do not require the parties to post margin and are subject to counterparty risk. OTC options also involve greater liquidity risk. The staff of the SEC takes the position that certain purchased OTC options, and assets used as cover for written OTC options, are illiquid. Derivatives on economic indicators generally are offered in an auction format and are booked and settled as OTC options. Options on futures contracts are discussed herein under “Futures and Options Thereon.”

If a written option expires unexercised, the Fund realizes a capital gain equal to the premium received at the time the option was written. If a purchased option expires unexercised, the Fund realizes a capital loss equal to the premium paid. Prior to the earlier of exercise or expiration, an exchange traded option may be closed out by an offsetting purchase or sale of an option of the same series (type, exchange, reference instrument, exercise price, and expiration). A capital gain will be realized from a closing purchase transaction if the cost of the closing option is less than the premium received from writing the option, or, if it is more, a capital loss will be realized. If the premium received from a closing sale transaction is more than the premium paid to purchase the option, the Fund will realize a capital gain or, if it is less, the Fund will realize a capital loss. The principal factors affecting the market value of a put or a call option include supply and demand, the current market price of the reference instrument in relation to the exercise price of the option, the volatility of the reference instrument, and the time remaining until the expiration date. There can be no assurance that a closing purchase or sale transaction can be consummated when desired.

Straddles are a combination of a call and a put written on the same reference instrument. A straddle is deemed to be covered when sufficient assets are deposited to meet the Fund’s immediate obligations. The same liquid assets may be used to cover both the call and put options where the exercise price of the call and put are the same, or the exercise price of the call is higher than that of the put. The Fund may also buy and write call options on the same reference instrument to cover its obligations. Because such combined options positions involve multiple trades, they result in higher transaction costs and may be more difficult to open or close. In an equity collar, the Fund simultaneously writes a call option and purchases a put option on the same instrument.

To the extent that the Fund writes a call option on an instrument it holds and intends to use such instrument as the sole means of “covering” its obligation under the call option, the Fund has, in return for the premium on the option, given up the opportunity to profit from a price increase in the instrument above the exercise price during the option period, but, as long as its obligation under such call option continues, has retained the risk of loss should the value of the reference instrument decline. If the Fund were unable to close out such a call option, it would not be able to sell the instrument unless the option expired without exercise. Uncovered calls have speculative characteristics and are riskier than covered calls because there is no instrument or cover held by the Fund that can act as a partial hedge.

The writer of an option has no control over the time when it may be required to fulfill its obligation under the option. Once an option writer has received an exercise notice, it cannot effect a closing purchase transaction in order to terminate its obligation under the option and must deliver the underlying reference instrument at the exercise price. If a put or call option purchased by the Fund is not sold when it has remaining value, and if the market price of the underlying security remains equal to or greater than the exercise price (in the case of a put), or remains less than or equal to the exercise price (in the case of a call), the Fund will lose the premium it paid for the option. Furthermore, if trading restrictions or suspensions are imposed on options markets, the Fund may be unable to close out a position.

Futures and Options Thereon. The Fund may engage in transactions in futures and options on futures. Futures are standardized, exchange-traded contracts that obligate a purchaser to take delivery, and a seller to make delivery, of a specific amount of an asset at a specified future date at a specified price. No price is paid upon entering into a futures contract. Rather, upon purchasing or selling a futures contract the Fund is required to deposit collateral (“margin”) equal to a percentage (generally less

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SAI dated April ___, 2017

than 10%) of the contract value. Each day thereafter until the futures position is closed, the Fund will pay additional margin representing any loss experienced as a result of the futures position the prior day or be entitled to a payment representing any profit experienced as a result of the futures position the prior day. Futures involve substantial leverage risk. The sale of a futures contract limits the Fund’s risk of loss from a decline in the market value of portfolio holdings correlated with the futures contract prior to the futures contract’s expiration date. In the event the market value of the Fund holdings correlated with the futures contract increases rather than decreases, however, the Fund will realize a loss on the futures position and a lower return on the Fund holdings than would have been realized without the purchase of the futures contract.

The purchase of a futures contract may protect the Fund from having to pay more for securities as a consequence of increases in the market value for such securities during a period when the Fund was attempting to identify specific securities in which to invest in a market the Fund believes to be attractive. In the event that such securities decline in value or the Fund determines not to complete an anticipatory hedge transaction relating to a futures contract, however, the Fund may realize a loss relating to the futures position.

The Fund is also authorized to purchase or sell call and put options on futures contracts including financial futures and stock indices. Generally, these strategies would be used under the same market and market sector conditions (i.e., conditions relating to specific types of investments) in which the Fund entered into futures transactions. The Fund may purchase put options or write call options on futures contracts and stock indices in lieu of selling the underlying futures contract in anticipation of a decrease in the market value of its securities. Similarly, the Fund can purchase call options, or write put options on futures contracts and stock indices, as a substitute for the purchase of such futures to hedge against the increased cost resulting from an increase in the market value of securities which the Fund intends to purchase.

Risks Associated with Futures. The primary risks associated with the use of futures contracts and options are (a) the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the futures contract or option; (b) possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (c) losses caused by unanticipated market movements, which are potentially unlimited; (d) the investment adviser’s inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; and (e) the possibility that the counterparty will default in the performance of its obligations.

Swap Agreements. Swap agreements are two-party contracts entered into primarily by institutional investors for periods ranging from a few weeks to more than one year. In a standard “swap” transaction, two parties agree to exchange the returns (or differentials in rates of return) earned or realized on particular predetermined investments or instruments, which can be adjusted for an interest factor. The gross returns to be exchanged or “swapped” between the parties are generally calculated with respect to a “notional amount,” i.e., the return on or increase in value of a particular dollar amount invested at a particular interest rate or in a “basket” of securities representing a particular index. Whether the Fund’s use of swap agreements or swaptions will be successful in furthering its investment objectives will depend on the investment adviser’s ability to predict correctly whether certain types of investments are likely to produce greater returns than other investments. Because they are two-party contracts and because they may have terms of greater than seven days, swap agreements may be considered to be illiquid. Moreover, the Fund bears the risk of loss of the amount expected to be received under a swap agreement in the event of the default or bankruptcy of a swap agreement counterparty. The Fund will enter into swap agreements only with counterparties that meet certain standards of creditworthiness. If there is a default by the other party to such a transaction, the Fund will have contractual remedies pursuant to the agreements related to the transaction. Swap agreements are also subject to the risk that the Fund will not be able to meet its obligations to the counterparty. The Fund, however, will segregate liquid assets equal to or greater than the market value of the liabilities under the swap agreement or the amount it would cost the Fund initially to make an equivalent direct investment, plus or minus any amount the Fund is obligated to pay or is to receive under the swap agreement. The swap market has grown substantially in recent years with a large number of banks and investment banking firms acting both as principals and as agents utilizing standardized swap documentation. As a result, the swap market has become relatively liquid. The swaps market is largely unregulated. It is possible that developments in the swaps market, including potential government regulation, could adversely affect the Fund’s ability to terminate existing swap agreements or to realize amounts to be received under such agreements.

Interest Rate Swaps, Caps and Floors. Interest rate swaps are OTC contracts in which each party agrees to make a periodic interest payment based on an index or the value of an asset in return for a periodic payment from the other party based on a different index or asset. The purchase of an interest rate floor entitles the purchaser, to the extent that a specified index falls below a predetermined interest rate, to receive payments of interest on a notional principal amount from the party selling such interest rate floor. The purchase of an interest rate cap entitles the purchaser, to the extent that a specified index rises above a predetermined interest rate, to receive payments of interest on a notional principal amount from the party selling such interest rate cap. The Fund usually will enter into interest rate swap transactions on a net basis (i.e., the two payment streams are netted out, with the Fund receiving or paying, as the case may be, only the net amount of the two payments). The net amount of the excess, if any, of the Fund’s obligations over its entitlements with respect to each interest rate swap will be accrued on a daily

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basis. If the interest rate swap transaction is entered into on other than a net basis, the full amount of the Fund’s obligations will be accrued on a daily basis. Certain federal income tax requirements may limit the Fund’s ability to engage in certain interest rate transactions.

OTC Derivatives. OTC derivative instruments involve an additional risk in that the issuer or counterparty may fail to perform its contractual obligations. Some derivative instruments are not readily marketable or may become illiquid under adverse market conditions. In addition, during periods of market volatility, an option or commodity exchange or swap execution facility or clearinghouse may suspend or limit trading in an exchange-traded derivative instrument, which may make the contract temporarily illiquid and difficult to price. Commodity exchanges may also establish daily limits on the amount that the price of a futures contract or futures option can vary from the previous day’s settlement price. Once the daily limit is reached, no trades may be made that day at a price beyond the limit. This may prevent the closing out of positions to limit losses. The staff of the SEC takes the position that certain purchased OTC options, and assets used as cover for written OTC options, are illiquid. The ability to terminate OTC derivative instruments may depend on the cooperation of the counterparties to such contracts. For thinly traded derivative instruments, the only source of price quotations may be the selling dealer or counterparty. In addition, certain provisions of the Code limit the use of derivative instruments.

Short Sales

The Fund may sell a security short if it owns at least an equal amount of the security sold short or another security convertible or exchangeable for an equal amount of the security sold short without payment of further compensation (a short sale against-the-box). If the price of the security in the short sale decreases, the Fund will realize a profit to the extent that the short sale price for the security exceeds the market price. If the price of the security increases, the Fund will realize a loss to the extent that the market price exceeds the short sale price. Selling securities short runs the risk of losing an amount greater than the initial investment therein.

Purchasing securities to close out the short position can itself cause the price of the securities to rise further, thereby exacerbating the loss. Short-selling exposes the Fund to unlimited risk with respect to that security due to the lack of an upper limit on the price to which an instrument can rise. Although the Fund reserves the right to utilize short sales, the Adviser is under no obligation to utilize short-sales at all.

When-Issued, Delayed Delivery and Forward Commitment Transactions

Securities may be purchased on a “forward commitment,” “when-issued” or “delayed delivery” basis (meaning securities are purchased or sold with payment and delivery taking place in the future) in order to secure what is considered to be an advantageous price and yield at the time of entering into the transaction. When the Fund agrees to purchase such securities, it assumes the risk of any decline in value of the security from the date of the agreement to purchase. The Fund does not earn interest on the securities it has committed to purchase until they are paid for and delivered on the settlement date.

From the time of entering into the transaction until delivery and payment is made at a later date, the securities that are the subject of the transaction are subject to market fluctuations. In forward commitment, when-issued or delayed delivery transactions, if the seller or buyer, as the case may be, fails to consummate the transaction the counterparty may miss the opportunity of obtaining a price or yield considered to be advantageous. However, no payment or delivery is made until payment is received or delivery is made from the other party to the transaction.

The Fund will make commitments to purchase when-issued securities only with the intention of actually acquiring the securities, but may sell such securities before the settlement date if it is deemed advisable as a matter of investment strategy.

Securities Lending

As described in the Prospectus, the Fund may lend a portion of its portfolio securities to broker-dealers or other institutional borrowers. Loans will be made only to organizations whose credit quality or claims paying ability is considered by the Adviser to be at least investment grade. All securities loans will be collateralized on a continuous basis by cash, cash equivalents (such as money market instruments) or U.S. Government securities having a value, marked to market daily, of at least 100% of the market value of the loaned securities. The Fund may receive loan fees in connection with loans that are collateralized by securities or on loans of securities for which there is special demand. The Fund may also seek to earn income on securities loans by reinvesting cash collateral in securities consistent with its investment objectives and policies, seeking to invest at rates that are higher than the “rebate” rate that it normally will pay to the borrower with respect to such cash collateral. Any such reinvestment will be subject to the investment policies, restrictions and risk considerations described in the Prospectus and in this SAI.

Securities loans may result in delays in recovering, or a failure of the borrower to return, the loaned securities. The defaulting borrower ordinarily would be liable to the Fund for any losses resulting from such delays or failures, and the collateral provided in connection with the loan normally would also be available for that purpose. Securities loans normally may be terminated by either the Fund or the borrower at any time. Upon termination and the return of the loaned securities, the Fund would be

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required to return the related cash or securities collateral to the borrower and it may be required to liquidate longer term portfolio securities in order to do so. To the extent that such securities have decreased in value, this may result in the Fund realizing a loss at a time when it would not otherwise do so. The Fund also may incur losses if it is unable to reinvest cash collateral at rates higher than applicable rebate rates paid to borrowers and related administrative costs. These risks are substantially the same as those incurred through investment leverage and will be subject to the investment policies, restrictions and risk considerations described in the Prospectus and in this SAI.

The Fund will receive amounts equivalent to any interest or other distributions paid on securities while they are on loan, and the Fund will not be entitled to exercise voting or other beneficial rights on loaned securities. The Fund will exercise its right to terminate loans and thereby regain these rights whenever the Adviser considers it to be in the Fund’s interest to do so, taking into account the related loss of reinvestment income and other factors.

Cybersecurity Risk

With the increased use of technologies by Fund service providers, such as the Internet to conduct business, the Fund is susceptible to operational, information security and related risks. In general, cyber incidents can result from deliberate attacks or unintentional events. Cyber attacks include, but are not limited to, gaining unauthorized access to digital systems (e.g., through “hacking” or malicious software coding) for purposes of misappropriating assets or sensitive information, corrupting data, or causing operational disruption. Cyber attacks may also be carried out in a manner that does not require gaining unauthorized access, such as causing denial-of-service attacks on websites (i.e., efforts to make network services unavailable to intended users). Cyber security failures or breaches by the Fund’s investment adviser or administrator and other service providers (including, but not limited to, the custodian or transfer agent), and the issuers of securities in which the Fund invests, have the ability to cause disruptions and impact business operations potentially resulting in financial losses, interference with the Fund’s ability to calculate its NAV, impediments to trading, violations of applicable privacy and other laws, regulatory fines, penalties, reputational damage, reimbursement or other compensation costs, or additional compliance costs. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future. While various Fund service providers have established business continuity plans and risk management systems intended to identify and mitigate cyber attacks, there are inherent limitations in such plans and systems including the possibility that certain risks have not been identified. Furthermore, the Fund cannot control the cyber security plans and systems put in place by service providers to the Fund and issuers in which the Fund invests. The Fund and its shareholders could be negatively impacted as a result.

Operational Risk

The Fund’s service providers, including the investment adviser, may experience disruptions or operating errors that could negatively impact the Fund. While service providers are expected to have appropriate operational risk management policies and procedures, their methods of operational risk management may differ from the Fund’s in the setting of priorities, the personnel and resources available or the effectiveness of relevant controls. It also is not possible for Fund service providers to identify all of the operational risks that may affect the Fund or to develop processes and controls to completely eliminate or mitigate their occurrence or effects.

Illiquid Securities

Illiquid securities include obligations legally restricted as to resale, and may include commercial paper issued pursuant to Section 4(a)(2) of the 1933 Act and securities eligible for resale pursuant to Rule 144A thereunder. Section 4(a)(2) and Rule 144A obligations may, however, be treated as liquid by the Adviser pursuant to procedures adopted by the Trustees, which require consideration of factors such as trading activity, availability of market quotations and number of dealers willing to purchase the security. Even if determined to be liquid, Rule 144A securities may increase the level of portfolio illiquidity if eligible buyers become uninterested in purchasing such securities.

It may be difficult to sell illiquid securities at a price representing fair value until such time as the securities may be sold publicly. It also may be more difficult to determine the fair value of such securities for purposes of computing the Fund’s net asset value. Where registration is required, a considerable period of time may elapse between a decision to sell the securities and the time when the Fund would be permitted to sell. Thus, the Fund may not be able to obtain as favorable a price as that prevailing at the time of the decision to sell. The Fund may incur additional expense when disposing of illiquid securities, including all or a portion of the cost to register the securities. The Fund also may acquire securities through private placements under which it may agree to contractual restrictions on the resale of such securities that are in addition to applicable legal restrictions. Such restrictions might prevent the sale of such securities at a time when such sale would otherwise be desirable.

At times, a portion of the Fund’s assets may be invested in securities as to which the Fund, by itself or together with other accounts managed by the Adviser and its affiliates, holds a major portion or all of such securities. Under adverse market or economic conditions or in the event of adverse changes in the financial condition of the issuer, the Fund could find it more difficult to sell such securities when the Adviser believes it advisable to do so or may be able to sell such securities only at prices

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lower than if such securities were more widely held. It may also be more difficult to determine the fair value of such securities for purposes of computing the Fund’s net asset value.

Asset Coverage Requirements

To the extent required by SEC guidelines, if a transaction creates a future obligation of the Fund to another party the Fund will: (1) cover the obligation by entering into an offsetting position or transaction; and/or (2) segregate cash and/or liquid securities with a value (together with any collateral posted with respect to the obligation) at least equal to the marked-to market value of the obligations. Assets used as cover or segregated cannot be sold while the position(s) requiring cover is open unless replaced with other appropriate assets. The types of transactions that may require asset coverage include (but are not limited to) reverse repurchase agreements, repurchase agreements, short sales, securities lending, forward contracts, certain options, forward commitments, futures contracts, when-issued securities, swap agreements, residual interest bonds, and participation in revolving credit facilities.

Temporary Investments

The Fund may invest in cash equivalents to invest daily cash balances or for temporary defensive purposes. Cash equivalents are highly liquid, short-term securities such as commercial paper, time deposits, certificates of deposit, short-term notes and short-term U.S. Government obligations.

Investment Restrictions

The following investment restrictions of the Fund are designated as fundamental policies and as such cannot be changed without the approval of the holders of a majority of the Fund’s outstanding voting securities, which as used in this SAI means the lesser of (a) 67% of the shares of the Fund present or represented by proxy at a meeting if the holders of more than 50% of the outstanding shares are present or represented at the meeting or (b) more than 50% of outstanding shares of the Fund. As a matter of fundamental policy the Fund may not:

(1)

Borrow money, except as permitted by the Investment Company Act of 1940, as amended (the “1940 Act”). The 1940 Act currently requires that any indebtedness incurred by a closed-end investment company have an asset coverage of at least 300%;

(2)

Issue senior securities, as defined in the 1940 Act, other than (a) preferred shares which immediately after issuance will have asset coverage of at least 200%, (b) indebtedness which immediately after issuance will have asset coverage of at least 300% or (c) the borrowings permitted by investment restriction (1) above. The 1940 Act currently defines “senior security” as any bond, debenture, note or similar obligation or instrument constituting a security and evidencing indebtedness and any stock of a class having priority over any other class as to distribution of assets or payment of dividends. Debt and equity securities issued by a closed-end investment company meeting the foregoing asset coverage provisions are excluded from the general 1940 Act prohibition on the issuance of senior securities;

(3)

Purchase securities on margin (but the Fund may obtain such short-term credits as may be necessary for the clearance of purchases and sales of securities). The purchase of investment assets with the proceeds of a permitted borrowing or securities offering will not be deemed to be the purchase of securities on margin;

(4)

Underwrite securities issued by other persons, except insofar as it may technically be deemed to be an underwriter under the Securities Act of 1933, as amended, in selling or disposing of a portfolio investment;

(5)

Make loans to other persons, except by (a) the acquisition of loan interests, debt securities and other obligations in which the Fund is authorized to invest in accordance with its investment objectives and policies, (b) entering into repurchase agreements and (c) lending its portfolio securities;

(6)

Purchase or sell real estate, although it may purchase and sell securities which are secured by interests in real estate and securities of issuers which invest or deal in real estate. The Fund reserves the freedom of action to hold and to sell real estate acquired as a result of the ownership of securities;

(7)

Purchase or sell physical commodities or contracts for the purchase or sale of physical commodities. Physical commodities do not include futures contracts with respect to securities, securities indices, currencies, interest or other financial instruments;

(8)

With respect to 75% of its total assets, invest more than 5% of its total assets in the securities of a single issuer or purchase more than 10% of the outstanding voting securities of a single issuer, except obligations issued or guaranteed by the U.S. government, its agencies or instrumentalities and except securities of other investment companies; and

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(9)

Invest 25% or more of its total assets in any single industry or group of industries (other than securities issued or guaranteed by the U.S. government or its agencies or instrumentalities).

The Fund may borrow money as a temporary measure for extraordinary or emergency purposes, including the payment of dividends and the settlement of securities transactions which otherwise might require untimely dispositions of Fund securities. The 1940 Act currently requires that the Fund have 300% asset coverage with respect to all borrowings other than temporary borrowings.

For purposes of construing restriction (9), a large economic or market sector shall not be construed as a group of industries.

The Fund has adopted the following nonfundamental investment policy which may be changed by the Board without approval of the Fund’s shareholders. As a matter of nonfundamental policy, the Fund may not make short sales of securities or maintain a short position, unless at all times when a short position is open the Fund either owns an equal amount of such securities or owns securities convertible into or exchangeable, without payment of any further consideration, for securities of the same issue as, and equal in amount to, the securities sold short.

The Fund may invest more than 10% of its total assets in one or more other management investment companies (or may invest in affiliated investment companies) to the extent permitted by section 12(d) of the 1940 Act and rules thereunder.

Whenever an investment policy or investment restriction set forth in the Prospectus or this SAI states a maximum percentage of assets that may be invested in any security or other asset or describes a policy regarding quality standards, such percentage limitation or standard shall be determined immediately after and as a result of the Fund’s acquisition of such security or asset. Accordingly, any later increase or decrease resulting from a change in values, assets or other circumstances or any subsequent rating change made by a rating service (or as determined by the Adviser if the security is not rated by a rating agency) will not compel the Fund to dispose of such security or other asset. Notwithstanding the foregoing, the Fund must always be in compliance with the borrowing policies set forth above.

TRUSTEES AND OFFICERS

The Board of Trustees of the Fund (the “Board”) is responsible for the overall management and supervision of the Fund’s affairs. The Board members and officers of the Fund are listed below. Except as indicated, each individual has held the office shown or other offices in the same company for the last five years. The “noninterested Trustees” consist of those Trustees who are not “interested persons” of the Fund, as that term is defined under the 1940 Act. The business address of each Board member and officer is Two International Place, Boston, Massachusetts 02110. As used in this SAI, “EVC” refers to Eaton Vance Corp., “EV” refers to Eaton Vance, Inc., “BMR” refers to Boston Management and Research, “EVMI” refers to Eaton Vance Management (International) Limited and “EVD” refers to Eaton Vance Distributors Inc. EVC and EV are the corporate parent and trustee, respectively, of Eaton Vance and BMR. EVMI is an indirect, wholly-owned subsidiary of EVC. EVD is a wholly-owned subsidiary of EVC. Each officer affiliated with Eaton Vance may hold a position with other Eaton Vance affiliates that is comparable to his or her position with Eaton Vance listed below.


Name and Year of Birth	Fund Position(s)⁽¹⁾	Term of Office and Length of Service	Principal Occupation(s) During Past Five Years and Other Relevant Experience	Number of Portfolios in Fund Complex Overseen By Trustee⁽²⁾	Other Directorships Held During Last Five Years⁽³⁾

Interested Trustee
THOMAS E. FAUST JR. 1958	Class I Trustee	Until 2018. 3 years. Since 2007.	Chairman, Chief Executive Officer and President of EVC, Director and President of EV, Chief Executive Officer and President of Eaton Vance and BMR, and Director of EVD and EVMI. Trustee and/or officer of 177 registered investment companies. Mr. Faust is an interested person because of his positions with BMR, Eaton Vance, EVC, EVD, EVMI and EV, which are affiliates of the Fund.	177	Director of EVC and Hexavest Inc. (investment management firm).

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Name and Year of Birth	Fund Position(s)⁽¹⁾	Term of Office and Length of Service	Principal Occupation(s) During Past Five Years and Other Relevant Experience	Number of Portfolios in Fund Complex Overseen By Trustee⁽²⁾	Other Directorships Held During Last Five Years⁽³⁾
Noninterested Trustees
SCOTT E. ESTON 1956	Class I Trustee	Until 2018. 3 years. Since 2011.	Private investor. Formerly held various positions at Grantham, Mayo, Van Otterloo and Co., L.L.C. (investment management firm) (1997-2009), including Chief Operating Officer (2002-2009), Chief Financial Officer (1997-2009) and Chairman of the Executive Committee (2002-2008); President and Principal Executive Officer, GMO Trust (open-end registered investment company) (2006-2009). Former Partner, Coopers and Lybrand L.L.P. (now PricewaterhouseCoopers) (a registered public accounting firm) (1987-1997). Mr. Eston has apprised the Board of Trustees that he intends to retire as a Trustee of all Eaton Vance funds effective September 30, 2017.	177	None
MARK R. FETTING 1954	Class III Trustee	Until 2017. 1 year. Since 2016.	Private investor. Formerly, held various positions at Legg Mason, Inc. (investment management firm) (2000-2012), including President, Chief Executive Officer, Director and Chairman (2008-2012), Senior Executive Vice President (2004-2008) and Executive Vice President (2001-2004). Formerly, President of Legg Mason family of funds (2001-2008). Formerly, Division President and Senior Officer of Prudential Financial Group, Inc. and related companies (investment management firm) (1991-2000).	177	Director and Chairman of Legg Mason, Inc. (2008-2012); Director/Trustee and Chairman of Legg Mason family of funds (14 funds) (2008-2012); and Director/Trustee of the Royce family of funds (35 funds) (2001-2012).
CYNTHIA E. FROST 1961	Class I Trustee	Until 2018. 3 years. Since 2014.	Private investor. Formerly, Chief Investment Officer of Brown University (university endowment) (2000-2012); Portfolio Strategist for Duke Management Company (university endowment manager) (1995-2000); Managing Director, Cambridge Associates (investment consulting company) (1989-1995); Consultant, Bain and Company (management consulting firm) (1987-1989); Senior Equity Analyst, BA Investment Management Company (1983-1985).	177	None
GEORGE J. GORMAN 1952	Class II Trustee	Until 2019. 3 years. Since 2014.	Principal at George J. Gorman LLC (consulting firm). Formerly, Senior Partner at Ernst & Young LLP (a registered public accounting firm) (1974-2009).	177	Formerly, Trustee of the BofA Funds Series Trust (11 funds) (2011-2014) and of the Ashmore Funds (9 funds) (2010-2014).

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Name and Year of Birth	Fund Position(s)⁽¹⁾	Term of Office and Length of Service	Principal Occupation(s) During Past Five Years and Other Relevant Experience	Number of Portfolios in Fund Complex Overseen By Trustee⁽²⁾	Other Directorships Held During Last Five Years⁽³⁾
VALERIE A. MOSLEY 1960	Class III Trustee	Until 2017. 3 years. Since 2014.	Chairwoman and Chief Executive Officer of Valmo Ventures (a consulting and investment firm). Former Partner and Senior Vice President, Portfolio Manager and Investment Strategist at Wellington Management Company, LLP (investment management firm) (1992-2012). Former Chief Investment Officer, PG Corbin Asset Management (1990-1992). Formerly worked in institutional corporate bond sales at Kidder Peabody (1986-1990).	177	Director of Dynex Capital, Inc. (mortgage REIT) (since 2013).
WILLIAM H. PARK 1947	Chairperson of the Board and Class II Trustee	Until 2019. 3 years. Chairperson of the Board since 2016 and Trustee since 2003.	Private investor. Formerly, Consultant (management and transactional) (2012-2014). Formerly, Chief Financial Officer, Aveon Group, L.P. (investment management firm) (2010-2011). Formerly, Vice Chairman, Commercial Industrial Finance Corp. (specialty finance company) (2006-2010). Formerly, President and Chief Executive Officer, Prizm Capital Management, LLC (investment management firm) (2002-2005). Formerly, Executive Vice President and Chief Financial Officer, United Asset Management Corporation (investment management firm) (1982-2001). Formerly, Senior Manager, Price Waterhouse (now PricewaterhouseCoopers) (a registered public accounting firm) (1972-1981).	177	None
HELEN FRAME PETERS 1948	Class III Trustee	Until 2017. 3 years. Since 2008.	Professor of Finance, Carroll School of Management, Boston College. Formerly, Dean, Carroll School of Management, Boston College (2000-2002). Formerly, Chief Investment Officer, Fixed Income, Scudder Kemper Investments (investment management firm) (1998-1999). Formerly, Chief Investment Officer, Equity and Fixed Income, Colonial Management Associates (investment management firm) (1991-1998).	177	Formerly, Director of BJ’s Wholesale Club, Inc. (wholesale club retailer) (2004-2011). Formerly, Trustee of SPDR Index Shares Funds and SPDR Series Trust (exchange traded funds) (2000-2009). Formerly, Director of Federal Home Loan Bank of Boston (a bank for banks) (2007-2009).
SUSAN J. SUTHERLAND 1957	Class II Trustee	Until 2019. 3 years. Since 2015.	Private investor. Formerly, Associate, Counsel and Partner at Skadden, Arps, Slate, Meagher & Flom LLP (law firm) (1982-2013).	177	Formerly, Director of Montpelier Re Holdings Ltd. (global provider of customized insurance and reinsurance products) (2013-2015).
HARRIETT TEE TAGGART 1948	Class II Trustee	Until 2019. 3 years. Since 2011.	Managing Director, Taggart Associates (a professional practice firm). Formerly, Partner and Senior Vice President, Wellington Management Company, LLP (investment management firm) (1983-2006).	177	Director of Albemarle Corporation (chemicals manufacturer) (since 2007) and The Hanover Group (specialty property and casualty insurance company) (since 2009). Formerly, Director of Lubrizol Corporation (specialty chemicals) (2007-2011).

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Name and Year of Birth	Fund Position(s)⁽¹⁾	Term of Office and Length of Service	Principal Occupation(s) During Past Five Years and Other Relevant Experience	Number of Portfolios in Fund Complex Overseen By Trustee⁽²⁾	Other Directorships Held During Last Five Years⁽³⁾
RALPH F. VERNI 1943	Class III Trustee	Until 2017. 3 years. Since 2005.	Consultant and private investor. Formerly, Chief Investment Officer (1982-1992), Chief Financial Officer (1988-1990) and Director (1982-1992), New England Life. Formerly, Chairperson, New England Mutual Funds (1982-1992). Formerly, President and Chief Executive Officer, State Street Management & Research (1992-2000). Formerly, Chairperson, State Street Research Mutual Funds (1992-2000). Formerly, Director, W.P. Carey, LLC (1998-2004) and First Pioneer Farm Credit Corp. (financial services cooperative) (2002-2006). Consistent with the Trustee retirement policy, Mr. Verni is currently expected to retire as a Trustee of all Eaton Vance funds effective July 1, 2017.	177	None
SCOTT E. WENNERHOLM 1959	Class I Trustee	Until 2018. 2 years. Since 2016.	Consultant at GF Parish Group (executive recruiting firm). Trustee at Wheelock College (postsecondary institution) (since 2012). Formerly, Chief Operating Officer and Executive Vice President at BNY Mellon Asset Management (investment management firm) (2005-2011). Formerly, Chief Operating Officer and Chief Financial Officer at Natixis Global Asset Management (investment management firm) (1997-2004). Formerly, Vice President at Fidelity Investments Institutional Services (investment management firm) (1994-1997).	177	None

⁽¹⁾

The Board of Trustees is divided into three classes, each class having a term of three years to expire on the date of the third annual meeting following its election.

⁽²⁾

Includes both master and feeder funds in a master-feeder structure.

⁽³⁾

During their respective tenures, the Trustees (except for Mmes. Frost and Sutherland and Messrs. Fetting, Gorman and Wennerholm) also served as Board members of one or more of the following funds (which operated in the years noted): eUnits^TM 2 Year U.S. Market Participation Trust: Upside to Cap/Buffered Downside (launched in 2012 and terminated in 2014); eUnits^TM 2 Year U.S. Market Participation Trust II: Upside to Cap/Buffered Downside (launched in 2012 and terminated in 2014); and Eaton Vance National Municipal Income Trust (launched in 1998 and terminated in 2009). However, Ms. Mosley did not serve as a Board member of eUnits^TM 2 Year U.S. Market Participation Trust: Upside to Cap/Buffered Downside (launched in 2012 and terminated in 2014).


Principal Officers who are not Trustees
Name and Year of Birth	Fund Position(s)	Term of Office and Length of Service	Principal Occupation(s) During Past Five Years

Edward J. Perkin 1972	President	Since 2017	Chief Equity Investment Officer and Vice President of Eaton Vance and BMR since 2014. Formerly, Chief Investment Officer, International and Emerging Markets Equity, and Managing Director, Portfolio Manager, Europe, EAFE and Global at Goldman Sachs Asset Management (2002-2014). Officer of 27 registered investment companies managed by Eaton Vance or BMR.
Maureen A. Gemma 1960	Vice President, Secretary and Chief Legal Officer	Vice President since 2011, Secretary since 2007 and Chief Legal Officer since 2008	Vice President of Eaton Vance and BMR. Officer of 177 registered investment companies managed by Eaton Vance or BMR. Also Vice President of Calvert Research and Management (“CRM”) and officer of 37 registered investment companies advised or administered by CRM since 2016.
James F. Kirchner 1967	Treasurer	Since 2013	Vice President of Eaton Vance and BMR. Officer of 177 registered investment companies managed by Eaton Vance or BMR. Also Vice President of CRM and officer of 37 registered investment companies advised or administered by CRM since 2016.
Paul M. O’Neil 1953	Chief Compliance Officer	Since 2004	Vice President of EVM and BMR. Officer of 177 registered investment companies managed by EVM or BMR.

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The Board has general oversight responsibility with respect to the business and affairs of the Fund. The Board has engaged an investment adviser and (if applicable) a sub-adviser (collectively the “adviser”) to manage the Fund and an administrator to administer the Fund and is responsible for overseeing such adviser and administrator and other service providers to the Fund. The Board is currently composed of twelve Trustees, including eleven Trustees who are not “interested persons” of the Fund, as that term is defined in the 1940 Act (each a “noninterested Trustee”). In addition to six regularly scheduled meetings per year, the Board holds special meetings or informal conference calls to discuss specific matters that may require action prior to the next regular meeting. As discussed below, the Board has established six committees to assist the Board in performing its oversight responsibilities.

The Board has appointed a noninterested Trustee to serve in the role of Chairperson. The Chairperson’s primary role is to participate in the preparation of the agenda for meetings of the Board and the identification of information to be presented to the Board with respect to matters to be acted upon by the Board. The Chairperson also presides at all meetings of the Board and acts as a liaison with service providers, officers, attorneys, and other Board members generally between meetings. The Chairperson may perform such other functions as may be requested by the Board from time to time. In addition, the Board may appoint a noninterested Trustee to serve in the role of Vice-Chairperson. The Vice-Chairperson has the power and authority to perform any or all of the duties and responsibilities of the Chairperson in the absence of the Chairperson and/or as requested by the Chairperson. Except for any duties specified herein or pursuant to the Fund’s Declaration of Trust or By-laws, the designation of Chairperson or Vice-Chairperson does not impose on such noninterested Trustee any duties, obligations or liability that is greater than the duties, obligations or liability imposed on such person as a member of the Board, generally.

The Fund is subject to a number of risks, including, among others, investment, compliance, operational, and valuation risks. Risk oversight is part of the Board’s general oversight of the Fund and is addressed as part of various activities of the Board and its Committees. As part of its oversight of the Fund, the Board directly, or through a Committee, relies on and reviews reports from, among others, Fund management, the adviser, the administrator, the principal underwriter, the Chief Compliance Officer (the “CCO”), and other Fund service providers responsible for day-to-day oversight of Fund investments, operations and compliance to assist the Board in identifying and understanding the nature and extent of risks and determining whether, and to what extent, such risks can or should be mitigated. The Board also interacts with the CCO and with senior personnel of the adviser, administrator, principal underwriter and other Fund service providers and provides input on risk management issues during meetings of the Board and its Committees. Each of the adviser, administrator, principal underwriter and the other Fund service providers has its own, independent interest and responsibilities in risk management, and its policies and methods for carrying out risk management functions will depend, in part, on its individual priorities, resources and controls. It is not possible to identify all of the risks that may affect the Fund or to develop processes and controls to eliminate or mitigate their occurrence or effects. Moreover, it is necessary to bear certain risks (such as investment-related risks) to achieve the Fund’s goals.

The Board, with the assistance of management and with input from the Board’s various committees, reviews investment policies and risks in connection with its review of Fund performance. The Board has appointed a Fund CCO who oversees the implementation and testing of the Fund compliance program and reports to the Board regarding compliance matters for the Fund and its principal service providers. In addition, as part of the Board’s periodic review of the advisory, subadvisory (if applicable), distribution and other service provider agreements, the Board may consider risk management aspects of their operations and the functions for which they are responsible. With respect to valuation, the Board approves and periodically reviews valuation policies and procedures applicable to valuing the Fund’s shares. The administrator, the investment adviser and the sub-adviser (if applicable) are responsible for the implementation and day-to-day administration of these valuation policies and procedures and provides reports to the Audit Committee of the Board and the Board regarding these and related matters. In addition, the Audit Committee of the Board or the Board receives reports periodically from the independent public accounting firm for the Fund regarding tests performed by such firm on the valuation of all securities, as well as with respect to other risks associated with mutual funds. Reports received from service providers, legal counsel and the independent public accounting firm assist the Board in performing its oversight function.

The Fund’s Declaration of Trust does not set forth any specific qualifications to serve as a Trustee. The Charter of the Governance Committee also does not set forth any specific qualifications, but does set forth certain factors that the Committee may take into account in considering noninterested Trustee candidates. In general, no one factor is decisive in the selection of an individual to join the Board. Among the factors the Board considers when concluding that an individual should serve on the Board are the following: (i) knowledge in matters relating to the mutual fund industry; (ii) experience as a director or senior officer of public companies; (iii) educational background; (iv) reputation for high ethical standards and professional integrity; (v) specific financial, technical or other expertise, and the extent to which such expertise would complement the Board members’ existing mix of skills, core competencies and qualifications; (vi) perceived ability to contribute to the ongoing functions of the Board, including the ability and commitment to attend meetings regularly and work collaboratively with other members of the Board; (vii) the ability to qualify as a noninterested Trustee for purposes of the 1940 Act and any other actual or potential

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conflicts of interest involving the individual and the Fund; and (viii) such other factors as the Board determines to be relevant in light of the existing composition of the Board.

Among the attributes or skills common to all Board members are their ability to review critically, evaluate, question and discuss information provided to them, to interact effectively with the other members of the Board, management, sub-advisers, other service providers, counsel and independent registered public accounting firms, and to exercise effective and independent business judgment in the performance of their duties as members of the Board. Each Board member’s ability to perform his or her duties effectively has been attained through the Board member’s business, consulting, public service and/or academic positions and through experience from service as a member of the Boards of the Eaton Vance family of funds (“Eaton Vance Fund Boards”) (and/or in other capacities, including for any predecessor funds), public companies, or non-profit entities or other organizations as set forth below. Each Board member’s ability to perform his or her duties effectively also has been enhanced by his or her educational background, professional training, and/or other life experiences.

In respect of each current member of the Board, the individual’s substantial professional accomplishments and experience, including in fields related to the operations of registered investment companies, were a significant factor in the determination that the individual should serve as a member of the Board. The following is a summary of each Board member’s particular professional experience and additional considerations that contributed to the Board’s conclusion that he or she should serve as a member of the Board:

Scott E. Eston. Mr. Eston has served as a member of the Eaton Vance Fund Boards since 2011 and is the Chairperson of the Contract Review Committee. He currently serves on the board and on the investment committee of Michigan State University Foundation, and on the investment advisory sub-committee of Michigan State University. From 1997 through 2009, Mr. Eston served in several capacities at Grantham, Mayo, Van Otterloo and Co. (“GMO”), including as Chairman of the Executive Committee and Chief Operating Officer and Chief Financial Officer, and also as the President and Principal Executive officer of GMO Trust, an affiliated open-end registered investment company. From 1978 through 1997, Mr. Eston was employed at Coopers & Lybrand L.L.P. (now PricewaterhouseCoopers) (since 1987 as a Partner).

Thomas E. Faust Jr. Mr. Faust has served as a member of the Eaton Vance Fund Boards since 2007. He is currently Chairman, Chief Executive Officer and President of EVC, Director and President of EV, Chief Executive Officer and President of Eaton Vance and BMR, and Director of EVD and EVMI. Mr. Faust has served as a Director of Hexavest Inc. since 2012 and of SigFig Wealth Management LLC since 2016. Mr. Faust previously served as an equity analyst, portfolio manager, Director of Equity Research and Management and Chief Investment Officer of Eaton Vance (1985-2007). He holds B.S. degrees in Mechanical Engineering and Economics from the Massachusetts Institute of Technology and an MBA from Harvard Business School. Mr. Faust has been a Chartered Financial Analyst since 1988.

Mark R. Fetting. Mr. Fetting has served as a member of the Eaton Vance Fund Boards since September 1, 2016. He has over 30 years of experience in the investment management industry as an executive and in various leadership roles. From 2000 through 2012, Mr. Fetting served in several capacities at Legg Mason, Inc., including most recently serving as President, Chief Executive Officer, Director and Chairman from 2008 to his retirement in 2012. He also served as a Director/Trustee and Chairman of the Legg Mason family of funds (2008-2012) and Director/Trustee of the Royce family of funds (2001-2012). From 2001 through 2008, Mr. Fetting also served as President of the Legg Mason family of funds. From 1991 through 2000, Mr. Fetting served as Division President and Senior Officer of Prudential Financial Group, Inc. and related companies. Early in his professional career, Mr. Fetting was a Vice President at T. Rowe Price and served in leadership roles within the firm’s mutual fund division from 1981 through 1987.

Cynthia E. Frost. Ms. Frost has served as a member of the Eaton Vance Fund Boards since 2014. From 2000 through 2012, Ms. Frost was the Chief Investment Officer of Brown University, where she oversaw the evaluation, selection and monitoring of the third party investment managers who managed the university’s endowment. From 1995-2000, Ms. Frost was a Portfolio Strategist for Duke Management Company, which oversaw Duke University’s endowment. Ms. Frost also served in various investment and consulting roles at Cambridge Associates (1989-1995), Bain and Company (1987-1989) and BA Investment Management Company (1983-1985). She serves as a member of an advisory board of Creciente Partners Investment Management, LLC, a manager of a hedge fund of funds , and has additional experience as a member of the investment committee of several non-profit organizations.

George J. Gorman. Mr. Gorman has served as a member of the Eaton Vance Fund Boards since 2014 and is the Chairperson of the Compliance Reports and Regulatory Matters Committee. From 1974 through 2009, Mr. Gorman served in various capacities at Ernst & Young LLP, including as a Senior Partner in the Asset Management Group (from 1988) specializing in managing engagement teams responsible for auditing mutual funds registered with the SEC, hedge funds and private equity funds. Mr. Gorman also has experience serving as an independent trustee of other mutual fund complexes, including the Bank of America Money Market Funds Series Trust (2011-2014) and the Ashmore Funds (2010-2014).

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Valerie A. Mosley. Ms. Mosley has served as a member of the Eaton Vance Fund Boards since 2014 and is the Chairperson of the Ad Hoc Committee for Closed-End Fund Matters. She currently owns and manages a consulting and investment firm, Valmo Ventures and is a Director of Progress Investment Management Company, a manager of emerging managers. From 1992 through 2012, Ms. Mosley served in several capacities at Wellington Management Company, LLP, an investment management firm, including as a Partner, Senior Vice President, Portfolio Manager and Investment Strategist. Ms. Mosley also served as Chief Investment Officer at PG Corbin Asset Management from 1990-1992 and worked in institutional corporate bond sales at Kidder Peabody from 1986-1990. Ms. Mosley is a Director of Dynex Capital, Inc., a mortgage REIT, where she serves on the board’s audit and investment committees. She also serves as a trustee or board member of several major non-profit organizations and endowments, including Mass Ventures, a quasi-public early-stage investment corporation active in Massachusetts, and New Profit, a non-profit venture philanthropy fund. She is a member of the Risk Audit Committee of the United Auto Workers Retiree Medical Benefits Trust and a member of the Investment Advisory Committee of New York State Common Retirement Fund. She is also an advisor to New Technology Ventures, a venture capital firm.

William H. Park. Mr. Park has served as a member of the Eaton Vance Fund Boards since 2003 and is the Independent Chairperson of the Board. Mr. Park was formerly a consultant from 2012-2014 and formerly the Chief Financial Officer of Aveon Group, L.P. from 2010-2011. Mr. Park also served as Vice Chairman of Commercial Industrial Finance Corp. from 2006-2010, as President and Chief Executive Officer of Prizm Capital Management, LLC from 2002-2005, as Executive Vice President and Chief Financial Officer of United Asset Management Corporation from 1982-2001 and as Senior Manager of Price Waterhouse (now PricewaterhouseCoopers) from 1972-1981.

Helen Frame Peters. Ms. Peters has served as a member of the Eaton Vance Fund Boards since 2008 and is the Chairperson of the Portfolio Management Committee. Ms. Peters is currently a Professor of Finance at Carroll School of Management, Boston College and was formerly Dean of Carroll School of Management from 2000-2002. Ms. Peters was previously a Director of BJ’s Wholesale Club, Inc. from 2004-2011. In addition, Ms. Peters was the Chief Investment Officer, Fixed Income at Scudder Kemper Investments from 1998-1999 and Chief Investment Officer, Equity and Fixed Income at Colonial Management Associates from 1991-1998. Ms. Peters also served as a Trustee of SPDR Index Shares Funds and SPDR Series Trust from 2000-2009 and as a Director of the Federal Home Loan Bank of Boston from 2007-2009.

Susan J. Sutherland. Ms. Sutherland has served as a member of the Eaton Vance Fund Boards since 2015. Ms. Sutherland also serves as a director of Hagerty Holding Corp., a leading provider of specialized automobile and marine insurance. Ms. Sutherland was a Director of Montpelier Re Holdings Ltd., a global provider of customized reinsurance and insurance products, from 2013 until its sale in 2015. From 1982 through 2013, Ms. Sutherland was an associate, counsel and then a partner in the Financial Institutions Group of Skadden, Arps, Slate, Meagher & Flom LLP, where she primarily represented U.S. and international insurance and reinsurance companies, investment banks and private equity firms in insurance-related corporate transactions. In addition, Ms. Sutherland is qualified as a Governance Fellow of the National Association of Corporate Directors and has also served as a board member of prominent non-profit organizations.

Harriett Tee Taggart. Ms. Taggart has served as a member of the Eaton Vance Fund Boards since 2011 and is the Chairperson of the Governance Committee. Ms. Taggart currently manages a professional practice, Taggart Associates. Since 2007, Ms. Taggart has been a Director of Albemarle Corporation, a specialty chemical company where she serves as a member of the Executive Compensation Committee. Since 2009 she has served as a Director of the Hanover Insurance Group, Inc. where she serves as Chair of the Nomination and Governance Committee. Ms. Taggart is also a trustee or member of several major non-profit boards, advisory committees and endowment investment companies. From 1983 through 2006, Ms. Taggart served in several capacities at Wellington Management Company, LLP, an investment management firm, including as a Partner, Senior Vice President and chemical industry sector portfolio manager. Ms. Taggart also served as a Director of the Lubrizol Corporation, a specialty chemicals manufacturer from 2007-2011.

Ralph F. Verni. Mr. Verni has served as a member of the Eaton Vance Fund Boards since 2005 and is the Chairperson of the Audit Committee. Mr. Verni was formerly the Chief Investment Officer from 1982-1992 , Chief Financial Officer from 1988-1990 and Director from 1982-1992 of New England Life. Mr. Verni was also the Chairperson of the New England Mutual Funds from 1982-1992; President and Chief Executive Officer of State Street Management & Research from 1992-2000; Chairperson of the State Street Research Mutual Funds from 1992-2000; Director of W.P. Carey, LLC from 1998-2004; and Director of First Pioneer Farm Credit Corp. from 2002-2006. Mr. Verni has been a Chartered Financial Analyst since 1977.

Scott E. Wennerholm. Mr. Wennerholm has served as a member of the Eaton Vance Fund Boards since September 1, 2016. He has over 30 years of experience in the financial services industry in various leadership and executive roles. Mr. Wennerholm served as Chief Operating Officer and Executive Vice President at BNY Mellon Asset Management from 2005-2011 .. He also served as Chief Operating Officer and Chief Financial Officer at Natixis Global Asset Management from 1997-

Eaton Vance Tax-Managed Buy-Write Income Fund

SAI dated April ___, 2017

2004 and was a Vice President at Fidelity Investments Institutional Services from 1994-1997. Mr. Wennerholm currently serves as a Trustee at Wheelock College, a postsecondary institution.

The Board (s) of the Fund has several standing Committees, including the Governance Committee, the Audit Committee, the Portfolio Management Committee, the Compliance Reports and Regulatory Matters Committee, the Contract Review Committee and the Ad Hoc Committee for Closed-End Fund Matters. Each of the Committees are comprised of only noninterested Trustees.

Mmes. Taggart (Chairperson), Frost, Mosley, Peters and Sutherland, and Messrs. Eston, Fetting, Gorman, Park, Verni and Wennerholm are members of the Governance Committee. The purpose of the Governance Committee is to consider, evaluate and make recommendations to the Board with respect to the structure, membership and operation of the Board and the Committees thereof, including the nomination and selection of noninterested Trustees and a Chairperson of the Board and the compensation of such persons. During the fiscal year ended December 31, 2016 , the Governance Committee convened six times.

The Governance Committee will, when a vacancy exists, consider a nominee for Trustee recommended by a shareholder, provided that such recommendation is submitted in writing to the Fund’s Secretary at the principal executive office of the Fund. Such recommendations must be accompanied by biographical and occupational data on the candidate (including whether the candidate would be an “interested person” of the Fund), a written consent by the candidate to be named as a nominee and to serve as Trustee if elected, record and ownership information for the recommending shareholder with respect to the Fund, and a description of any arrangements or understandings regarding recommendation of the candidate for consideration.

Messrs. Verni (Chairperson), Eston, Gorman, Park and Wennerholm are members of the Audit Committee. The Board has designated Mr. Park, a noninterested Trustee, as audit committee financial expert. The Audit Committee’s purposes are to (i) oversee the Fund’s accounting and financial reporting processes, its internal control over financial reporting, and, as appropriate, the internal control over financial reporting of certain service providers; (ii) oversee or, as appropriate, assist Board oversight of the quality and integrity of the Fund’s financial statements and the independent audit thereof; (iii) oversee, or, as appropriate, assist Board oversight of, the Fund’s compliance with legal and regulatory requirements that relate to the Fund’s accounting and financial reporting, internal control over financial reporting and independent audits; (iv) approve prior to appointment the engagement and, when appropriate, replacement of the independent registered public accounting firm, and, if applicable, nominate the independent registered public accounting firm to be proposed for shareholder ratification in any proxy statement of the Fund; (v) evaluate the qualifications, independence and performance of the independent registered public accounting firm and the audit partner in charge of leading the audit; and (vi) prepare, as necessary, audit committee reports consistent with the requirements of applicable SEC and stock exchange rules for inclusion in the proxy statement of the Fund. During the fiscal year ended December 31, 2016 , the Audit Committee convened thirteen times.

Messrs. Eston (Chairperson), Fetting, Gorman, Park and Wennerholm, and Mmes. Frost, Mosley, Peters, Sutherland and Taggart are members of the Contract Review Committee. The purposes of the Contract Review Committee are to consider, evaluate and make recommendations to the Board concerning the following matters: (i) contractual arrangements with each service provider to the Fund, including advisory, sub-advisory, transfer agency, custodial and fund accounting, distribution services and administrative services; (ii) any and all other matters in which any service provider (including Eaton Vance or any affiliated entity thereof) has an actual or potential conflict of interest with the interests of the Fund; and (iii) any other matter appropriate for review by the noninterested Trustees, unless the matter is within the responsibilities of the other Committees of the Board. During the fiscal year ended December 31, 2016 , the Contract Review Committee convened eight times.

Mmes. Peters (Chairperson), Frost and Mosley and Mr. Fetting are members of the Portfolio Management Committee. The purposes of the Portfolio Management Committee are to: (i) assist the Board in its oversight of the portfolio management process employed by the Fund and its investment adviser and sub-adviser(s), if applicable, relative to the Fund’s stated objective(s), strategies and restrictions; (ii) assist the Board in its oversight of the trading policies and procedures and risk management techniques applicable to the Fund; and (iii) assist the Board in its monitoring of the performance results of all funds and portfolios, giving special attention to the performance of certain funds and portfolios that it or the Board identifies from time to time. During the fiscal year ended December 31, 2016 , the Portfolio Management Committee convened eight times.

Messrs. Gorman (Chairperson), Eston, Verni and Wennerholm, and Mmes .. Sutherland and Taggart are members of the Compliance Reports and Regulatory Matters Committee. The purposes of the Compliance Reports and Regulatory Matters Committee are to: (i) assist the Board in its oversight role with respect to compliance issues and certain other regulatory matters affecting the Fund; (ii) serve as a liaison between the Board and the Fund’s CCO; and (iii) serve as a “qualified legal compliance committee” within the rules promulgated by the SEC. During the fiscal year ended December 31, 2016 , the Compliance Reports and Regulatory Matters Committee convened ten times.

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Ms. Mosley (Chairperson) and Messrs. Gorman and Park are members of the Ad Hoc Committee for Closed-End Fund Matters. The purpose of the Ad Hoc Committee for Closed-End Fund Matters is to consider, evaluate and make recommendations to the Board with respect to issues specifically related to Eaton Vance Closed-End Funds. During the fiscal year ended December 31, 2016 , the Ad Hoc Committee for Closed-End Fund Matters convened one time ..

Share Ownership. The following table shows the dollar range of equity securities beneficially owned by each Trustee in the Fund and in the Eaton Vance family of funds overseen by the Trustee as of December 31, 2016 .


Name of Trustee	Dollar Range of Equity Securities Beneficially Owned in the Fund	Aggregate Dollar Range of Equity Securities Beneficially Owned in Funds Overseen by Trustee in the Eaton Vance Family of Funds
Interested Trustee
Thomas E. Faust Jr.	None	Over $100,000
Noninterested Trustees
Scott E. Eston	None	Over $100,000
Mark R. Fetting⁽¹⁾	None	Over $100,000
Cynthia E. Frost	None	Over $100,000 ⁽²⁾
George J. Gorman	None	Over $100,000
Valerie A. Mosley	None	Over $100,000
William H. Park	None	Over $100,000
Helen Frame Peters	None	Over $100,000
Susan J. Sutherland	None	Over $100,000 ⁽²⁾
Harriett Tee Taggart	None	Over $100,000
Ralph F. Verni	None	Over $100,000
Scott E. Wennerholm⁽¹⁾	None	None

⁽¹⁾Messrs. Fetting and Wennerholm began serving as Trustees effective September 1, 2016.

⁽²⁾ Includes shares which may be deemed to be beneficially owned through the Trustee Deferred Compensation Plan.

As of December 31, 2016 , no noninterested Trustee or any of their immediate family members owned beneficially or of record any class of securities of EVC, EVD or any person controlling, controlled by or under common control with EVC or EVD.

During the calendar years ended December 31, 2015 and December 31, 2016 , no noninterested Trustee (or their immediate family members) had:

Any direct or indirect interest in Eaton Vance, EVC, EVD, or any person controlling, controlled by or under common control with EVC or EVD;

Any direct or indirect material interest in any transaction or series of similar transactions with (i) the Fund ; (ii) another fund managed by EVC, distributed by EVD or a person controlling, controlled by or under common control with EVC or EVD; (iii) EVC or EVD; (iv) a person controlling, controlled by or under common control with EVC or EVD; or (v) an officer of any of the above; or

Any direct or indirect relationship with (i) the Fund ; (ii) another fund managed by EVC, distributed by EVD or a person controlling, controlled by or under common control with EVC or EVD; (iii) EVC or EVD; or (iv) a person controlling, controlled by or under common control with EVC or EVD; or (v) an officer of any of the above.

During the calendar years ended December 31, 2015 and December 31, 2016 , no officer of EVC, EVD or any person controlling, controlled by or under common control with EVC or EVD served on the board of directors of a company where a noninterested Trustee of the Fund or any of their immediate family members served as an officer.

Eaton Vance Tax-Managed Buy-Write Income Fund

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Noninterested Trustees may elect to defer receipt of all or a percentage of their annual fees in accordance with the terms of a Trustees Deferred Compensation Plan (the “Deferred Compensation Plan”). Under the Deferred Compensation Plan, an eligible Board member may elect to have his or her deferred fees invested in the shares of one or more funds in the Eaton Vance family of funds, and the amount paid to the Board members under the Deferred Compensation Plan will be determined based upon the performance of such investments. Deferral of Board member’s fees in accordance with the Deferred Compensation Plan will have a negligible effect on the assets, liabilities, and net income of a participating fund or portfolio, and do not require that a participating Board member be retained. There is no retirement plan for Board members.

The fees and expenses of the Board members of the Fund are paid by the Fund. (A Board member of the Fund who is a member of the Eaton Vance organization receives no compensation from the Fund.) During the fiscal year ended December 31, 2016 , the Board members of the Fund earned the following compensation in their capacities as Board members from the Fund. For the year ended December 31, 2016 , the Board members earned the following compensation in their capacities as Board members of the funds in the Eaton Vance fund complex⁽¹⁾:


Source of Compensation	Scott E. Eston	Mark R. Fetting	Cynthia E. Frost	George J. Gorman	Valerie A. Mosley	William H. Park	Helen Frame Peters	Susan J. Sutherland	Harriett Tee Taggart	Ralph F. Verni	Scott E. Wennerholm
Fund	$2,274	$2,064	$2,064 ⁽²⁾	$2,274	$2,134	$2,436	$2,274	$2,064 ⁽³⁾	$2,274	$2,776	$2,064
Fund and Fund Complex⁽¹⁾	$ 325,000	$ 295,000	$ 295,000 ⁽⁴⁾	$ 325,000	$ 305,000	$ 348,750	$ 325,000	$ 295,000 ⁽⁵⁾	$ 325,000	$ 396,250	$ 295,000

⁽¹⁾

As of March 27, 2017 , the Eaton Vance fund complex consists of 177 registered investment companies or series thereof. Messrs. Fetting and Wennerholm began serving as Trustees effective September 1, 2016, and thus the compensation figures listed for the Fund and the Fund and Fund Complex are estimated based on amounts each would have received if they has been Trustees for the full fiscal year ended December 31, 2016 and for the full calendar year ended December 31, 2016.

⁽²⁾

Includes $1, 166 of deferred compensation.

⁽³⁾

Includes $2, 064 of deferred compensation.

⁽⁴⁾

Includes $ 160 ,000 of deferred compensation.

⁽⁵⁾

Includes $ 283,167 of deferred compensation.

Proxy Voting Policy

The Board adopted a proxy voting policy and procedures (the “Fund Policy”), pursuant to which the Board has delegated proxy voting responsibility to the Adviser and adopted the Adviser’s proxy voting policies and procedures (the “Adviser Policies”). An independent proxy voting service has been retained to assist in the voting of Fund proxies through the provision of vote analysis, implementation and recordkeeping and disclosure services. The members of the Board will review the Fund’s proxy voting records from time to time and will annually consider approving the Adviser Policies for the upcoming year. In the event that a material conflict of interest exists between the Fund’s shareholders and the Adviser or any of its affiliates or any affiliate of the Fund, the Adviser will generally refrain from voting the proxies related to the companies giving rise to such conflict until it notifies and consults with the appropriate Board , or any committee, sub-committee or group of Independent Trustees identified by the Board concerning the material conflict .. The Fund’s and the Adviser’s Proxy Voting Policies and Procedures are attached as Appendix B to this SAI. Pursuant to certain provisions of the 1940 Act and certain exemptive orders relating to funds investing in other funds, a Fund may be required or may elect to vote its interest in another fund in the same proportion as the holders of all other shares of that fund. Information on how the Fund voted proxies relating to portfolio securities during the most recent 12-month period ended June 30 is available (1) without charge, upon request, by calling 1-800-262-1122, and (2) on the SEC’s website at http://www.sec.gov.

INVESTMENT ADVISORY AND OTHER SERVICES

The Investment Adviser

Eaton Vance, its affiliates and its predecessor companies have been managing assets of individuals and institutions since 1924 and of investment companies since 1931. They maintain a large staff of experienced fixed-income, senior loan and equity investment professionals to service the needs of their clients. The equity group covers stocks ranging from blue chip to emerging growth companies. The fixed-income group focuses on all kinds of taxable investment-grade and high-yield securities, tax-exempt investment-grade and high-yield securities, and U.S. government securities. The senior loan group focuses on senior floating rate loans, unsecured loans and other floating rate debt securities such as notes, bonds and asset backed securities. Eaton Vance and its affiliates act as adviser to a family of mutual funds, and individual and various institutional accounts, including corporations, hospitals, retirement plans, universities, foundations and trusts.

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The Fund will be responsible for all of its costs and expenses not expressly stated to be payable by Eaton Vance under the Investment Advisory Agreement (the “Advisory Agreement ”) or the Amended and Restated Administrative Services Agreement (the “Administration Agreement”). Such costs and expenses to be borne by the Fund include, without limitation: (i) expenses of maintaining the Fund and continuing its existence; (ii) commissions, fees and other expenses connected with the acquisition and disposition of securities and other investments; (iii) auditing, accounting and legal expenses; (iv) taxes and interest; (v) governmental fees; (vi) expenses of repurchase and redemption (if any) of shares, including all expenses incurred in conducting repurchase and tender offers for the purpose of repurchasing Fund shares; (vii) expenses of registering and qualifying the Fund and its shares under federal and state securities laws and of preparing registration statements and amendments for such purposes, and fees and expenses of registering and maintaining registrations of the Fund under state securities laws; (viii) registration of the Fund under the Investment Company Act of 1940; (ix) expenses of reports and notices to shareholders and of meetings of shareholders and proxy solicitations therefor; (x) expenses of reports to regulatory bodies; (xi) insurance expenses; (xii) association membership dues; (xiii) fees, expenses and disbursements of custodians and subcustodians for all services to the Fund (including without limitation safekeeping of funds, securities and other investments, keeping of books and accounts and determination of net asset values); (xiv) fees, expenses and disbursements of transfer agents, dividend disbursing agents, shareholder servicing agents and registrars for all services to the Fund; (xv) expenses of listing shares with a stock exchange; (xvi) any direct charges to shareholders approved by the Trustees of the Fund; (xvii) compensation and expenses of Trustees of the Fund who are not members of the Administrator’s organization; (xviii) all payments to be made and expenses to be assumed by the Fund in connection with the distribution of Fund shares; (xix) any pricing and valuation services employed by the Fund to value its investments including primary and comparative valuation services; (xx) any investment advisory, sub-advisory or similar management fee payable by the Fund; (xxi) all expenses incurred in connection with the Fund’s use of a line of credit, or issuing and maintaining preferred shares; and (xxii) such non-recurring items as may arise, including expenses incurred in Fund connection with litigation, proceedings and claims and the obligation of the Fund to indemnify its Trustees and officers with respect thereto.

Pursuant to the Advisory Agreement between the Adviser and the Fund, the Fund has agreed to pay an investment advisory fee, payable on a monthly basis, at an annual rate of 1.00% of the average daily gross assets of the Fund. Gross assets of the Fund means total assets of the Fund, including any form of investment leverage that the Fund may in the future determine to utilize, minus all accrued expenses incurred in the normal course of operations, but not excluding any liabilities or obligations attributable to any future investment leverage obtained through (i) indebtedness of any type (including, without limitation, borrowing through a credit facility/commercial paper program or the issuance debt securities), (ii) the issuance of preferred shares or other similar preference securities, (iii) the reinvestment of collateral received for securities loaned in accordance with the Fund’s investment objectives and policies and/or (iv) any other means.

As of December 31 , 2016, the Fund had net assets of $ 382, 920,671 .. For the fiscal years ended December 31 , 2016, 2015 and 2014 , the Fund incurred $3, 749,750, $3, 958,235 and $4,009,100 , respectively, in advisory fees.

Pursuant to a Sub-Advisory Agreement between the Adviser and the Sub-Adviser, Eaton Vance has delegated a portion of the investment management to Parametric. Eaton Vance pays Parametric a portion of its advisory fee for sub-advisory services provided to the Fund.

For the fiscal years ended December 31, 2016, 2015 and 2014, Parametric received $937,437, $989,559 and $1,002,275, respectively, in sub-advisory fees.

Pursuant to the Administration Agreement, based on the current level of compensation payable to Eaton Vance by the Fund under the Advisory Agreement, Eaton Vance receives no compensation from the Fund in respect of the services rendered and the facilities provided as administrator under the Administration Agreement.

The Advisory Agreement with the Adviser continues in effect indefinitely so long as such continuance is approved at least annually (i) by the vote of a majority of the noninterested Trustees of the Fund or of the Adviser, such vote being cast in person at a meeting specifically called for the purpose of voting on such approval and (ii) by the Board of Trustees of the Fund or by vote of a majority of the outstanding shares of the Fund. The Fund’s Administration Agreement continues in effect from year to year so long as such continuance is approved at least annually by the vote of a majority of the Fund’s Trustees. Each agreement may be terminated at any time without penalty on sixty (60) days’ written notice by the Trustees of the Fund or Eaton Vance, as applicable, or by vote of the majority of the outstanding shares of the Fund. Each agreement will terminate automatically in the event of its assignment. Each agreement provides that, in the absence of willful misfeasance, bad faith, gross negligence or reckless disregard of its obligations or duties to the Fund under such agreements on the part of Eaton Vance, Eaton Vance shall not be liable to the Fund for any loss incurred, to the extent not covered by insurance.

Eaton Vance Tax-Managed Buy-Write Income Fund

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The Advisory Agreement provides that Eaton Vance may engage one or more investment sub-advisers to assist with some or all aspects of the management of the Fund’s investments subject to such approvals as are required under the 1940 Act. Pursuant to these provisions, Eaton Vance has engaged Parametric as a sub-adviser to structure and manage the Fund’s common stock portfolio, including tax harvesting and other tax management techniques. The Advisory Agreement provides that Eaton Vance may terminate any sub-advisory agreement entered into and directly assume any functions performed by the sub-adviser, upon approval of the Board of Trustees, without the need for approval of the shareholders of the Fund.

Eaton Vance is a business trust organized under the laws of The Commonwealth of Massachusetts. EV serves as trustee of Eaton Vance. EV and Eaton Vance are wholly-owned subsidiaries of EVC, a Maryland corporation and publicly-held holding company. BMR is an indirect subsidiary of EVC. EVC through its subsidiaries and affiliates engages primarily in investment management, administration and marketing activities. The Directors of EVC are Thomas E. Faust Jr., Ann E. Berman, Leo I. Higdon, Jr., Brian D. Langstraat, Dorothy E. Puhy, Winthrop H. Smith, Jr. and Richard A. Spillane, Jr. All shares of the outstanding Voting Common Stock of EVC are deposited in a Voting Trust, the Voting Trustees of which are Mr. Faust, Jeffrey P. Beale, Craig R. Brandon, Daniel C. Cataldo, Michael A. Cirami, Cynthia J. Clemson, James H. Evans, Maureen A. Gemma, Laurie G. Hylton, Mr. Langstraat, Frederick S. Marius, David C. McCabe, Scott H. Page, Edward J. Perkin, Lewis R. Piantedosi, Charles B. Reed, Craig P. Russ, John L. Shea, Eric A. Stein, Payson F. Swaffield, Michael W. Weilheimer, R. Kelly Williams and Matthew J. Witkos (all of whom are officers of Eaton Vance or its affiliates). The Voting Trustees have unrestricted voting rights for the election of Directors of EVC. All of the outstanding voting trust receipts issued under said Voting Trust are owned by certain of the officers of BMR and Eaton Vance who may also be officers, or officers and Directors of EVC and EV. As indicated under “Management and Organization,” all of the officers of the Fund (as well as Mr. Faust who is also a Trustee) hold positions in the Eaton Vance organization.

The Sub-Adviser

Parametric acts as an investment sub-adviser to the Fund subject to the supervision of the Fund’s Board of Trustees and the Adviser and structures and manages the Fund’s common stock portfolio, including tax harvesting and other tax management techniques, pursuant to a sub-advisory agreement between the Adviser and Parametric (the “Sub-Advisory Agreement”). Eaton Vance pays Parametric a portion of its advisory fee for sub-advisory services provided to the Fund.

Parametric’s principal office is located at 1918 Eighth Avenue, Suite 3100, Seattle, WA 98101. Parametric is a Seattle, Washington based investment manager that has been providing investment advisory services since its formation in 1987. Parametric serves its clients through Investment Centers located in Seattle, WA , Minneapolis, MN and Westport, CT. In addition, in order to meet the needs of its clients, Parametric has offices in Boston, MA and Sydney, Australia. Parametric managed approximately $178. 6 billion in assets as of December 31 , 2016. Parametric is a wholly-owned subsidiary of EVC.

The Sub-Advisory Agreement with Parametric continues in effect indefinitely so long as such continuance is approved at least annually (i) by the Fund’s Board of Trustees or by the holders of a majority of its outstanding voting securities and (ii) by a majority of the Trustees who are not “interested persons” (as defined in the 1940 Act) of any party to the Sub-Advisory Agreement, by vote cast in person at a meeting called for the purpose of voting on such approval. The Sub-Advisory Agreement terminates automatically on its assignment and may be terminated without penalty on sixty (60) days’ written notice at the option of either the Adviser, by the Fund’s Board of Trustees or by a vote of a majority (as defined in the 1940 Act) of the Fund’s outstanding shares or by Parametric upon three (3) months’ notice. As discussed above, Eaton Vance may terminate the Sub-Advisory Agreement with Parametric and directly assume responsibility for the services provided by Parametric upon approval by the Board of Trustees without the need for approval of the shareholders of the Fund.

The Sub-Advisory Agreement with Parametric provides that in the absence of willful misfeasance, bad faith, gross negligence or reckless disregard for its obligations and duties thereunder, Parametric is not liable for any error or judgment or mistake of law or for any loss suffered by the Fund.

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Portfolio Managers

The portfolio managers of the Fund are listed below. The following table shows, as of the Fund’s most recent fiscal year end , the number of accounts each portfolio manager managed in each of the listed categories and the total assets (in millions of dollars) in the accounts managed within each category. The table also shows the number of accounts with respect to which the advisory fee is based on the performance of the account, if any, and the total assets (in millions of dollars) in those accounts.


	Number of All Accounts	Total Assets of All Accounts	Number of Accounts Paying a Performance Fee	Total Assets of Accounts Paying a Performance Fee
Michael A. Allison
Registered Investment Companies	15	$ 25,774.5	0	$0
Other Pooled Investment Vehicles	14	$ 12,705.4 ⁽¹⁾	0	$0
Other Accounts	17	$ 42.0	0	$0
Thomas C. Seto
Registered Investment Companies	37	$ 23,044.2 ⁽²⁾	0	$0
Other Pooled Investment Vehicles	12	$ 3,579.0	0	$0
Other Accounts	11,766	$ 67,418.2 ⁽³⁾	2	$974.5

⁽¹⁾

Certain of these “Other Pooled Investment Vehicles” invest a substantial portion of their assets either in a registered investment company or in a separate pooled investment vehicle managed by this portfolio manager or another Eaton Vance portfolio manager.

⁽²⁾

This portfolio manager provides investment advice with respect to only a portion of the total assets of certain of these accounts. Only the assets allocated to this portfolio manager as of the Fund’s most recent fiscal year end are reflected in the table.

⁽³⁾

For “Other Accounts” that are part of a wrap account program, the number of accounts is the number of sponsors for which the portfolio manager provides advisory services rather than the number of individual customer accounts within each wrap account program.

The following table shows the dollar range of Fund shares beneficially owned by each portfolio manager as of the Fund’s most recent fiscal year end and in the Eaton Vance family of funds as of December 31, 2016 ..


Portfolio Manager	Dollar Range of Equity Securities Beneficially Owned in the Fund	Aggregate Dollar Range of Equity Securities Beneficially Owned in the Eaton Vance Family of Funds
Michael A. Allison	None	Over $1,000,000
Thomas C. Seto	None	$500,001 - $1,000,000

It is possible that conflicts of interest may arise in connection with a portfolio manager’s management of the Fund’s investments on the one hand and the investments of other accounts for which a portfolio manager is responsible on the other. For example, a portfolio manager may have conflicts of interest in allocating management time, resources and investment opportunities among the Fund and other accounts he advises. In addition, due to differences in the investment strategies or restrictions between the Fund and the other accounts, the portfolio manager may take action with respect to another account that differs from the action taken with respect to the Fund. In some cases, another account managed by a portfolio manager may compensate the investment adviser based on the performance of the securities held by that account. The existence of such a performance based fee may create additional conflicts of interest for the portfolio manager in the allocation of management time, resources and investment opportunities. Whenever conflicts of interest arise, the portfolio manager will endeavor to exercise his discretion in a manner that he believes is equitable to all interested persons. The investment adviser and sub-adviser have adopted several policies and procedures designed to address these potential conflicts including a code of ethics and policies that govern the investment adviser’s and sub-adviser’s trading practices, including among other things the aggregation and allocation of trades among clients, brokerage allocations, cross trades and best execution.

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Compensation Structure of Eaton Vance

Compensation of the Adviser’s portfolio managers and other investment professionals has three primary components: (1) a base salary, (2) an annual cash bonus, and (3) annual non-cash compensation consisting of options to purchase shares of EVC’s nonvoting common stock , restricted shares of EVC’s nonvoting common stock and a Deferred Alpha Incentive Plan, which pays a deferred cash award tied to future excess returns in certain equity strategy portfolios .. The Adviser’s investment professionals also receive certain retirement, insurance and other benefits that are broadly available to the Adviser’s employees. Compensation of the Adviser’s investment professionals is reviewed primarily on an annual basis. Cash bonuses, stock-based compensation awards, and adjustments in base salary are typically paid or put into effect at or shortly after the October 31st fiscal year-end of EVC.

Eaton Vance’s Method to Determine Compensation

The Adviser compensates its portfolio managers based primarily on the scale and complexity of their portfolio responsibilities and the total return performance of managed funds and accounts versus the benchmark(s) stated in the prospectus, as well as an appropriate peer group (as described below). In addition to rankings within peer groups of funds on the basis of absolute performance, consideration may also be given to relative risk-adjusted performance. Risk-adjusted performance measures include, but are not limited to, the Sharpe ratio (Sharpe Ratio uses standard deviation and excess return to determine reward per unit of risk). Performance is normally based on periods ending on the September 30th preceding fiscal year end. Fund performance is normally evaluated primarily versus peer groups of funds as determined by Lipper Inc. and/or Morningstar, Inc. When a fund’s peer group as determined by Lipper or Morningstar is deemed by the Adviser’s management not to provide a fair comparison, performance may instead be evaluated primarily against a custom peer group or market index. In evaluating the performance of a fund and its manager, primary emphasis is normally placed on three-year performance, with secondary consideration of performance over longer and shorter periods. A portion of the compensation payable to equity portfolio managers and investment professionals will be determined based on the ability of one or more accounts managed by such manager to achieve a specified target average annual gross return over a three year period in excess of the account benchmark. The cash bonus to be payable at the end of the three year term will be established at the inception of the term and will be adjusted positively or negatively to the extent that the average annual gross return varies from the specified target return. For funds that are tax-managed or otherwise have an objective of after-tax returns, performance is measured net of taxes. For other funds, performance is evaluated on a pre-tax basis. For funds with an investment objective other than total return (such as current income), consideration will also be given to the fund’s success in achieving its objective. For managers responsible for multiple funds and accounts, investment performance is evaluated on an aggregate basis, based on averages or weighted averages among managed funds and accounts. Funds and accounts that have performance-based advisory fees are not accorded disproportionate weightings in measuring aggregate portfolio manager performance.

The compensation of portfolio managers with other job responsibilities (such as heading an investment group or providing analytical support to other portfolios) will include consideration of the scope of such responsibilities and the managers’ performance in meeting them.

The Adviser seeks to compensate portfolio managers commensurate with their responsibilities and performance, and competitive with other firms within the investment management industry. The Adviser participates in investment-industry compensation surveys and utilizes survey data as a factor in determining salary, bonus and stock-based compensation levels for portfolio managers and other investment professionals. Salaries, bonuses and stock-based compensation are also influenced by the operating performance of the Adviser and its parent company. The overall annual cash bonus pool is generally based on a substantially fixed percentage of pre-bonus adjusted operating income. While the salaries of the Adviser’s portfolio managers are comparatively fixed, cash bonuses and stock-based compensation may fluctuate significantly from year to year, based on changes in manager performance and other factors as described herein. For a high performing portfolio manager, cash bonuses and stock-based compensation may represent a substantial portion of total compensation.

Compensation Structure of Parametric

Compensation of Parametric portfolio managers and other investment professionals has three primary components: (1) a base salary, (2) an annual cash bonus, and (3) annual stock-based compensation awards .. Parametric investment professionals also receive certain retirement, insurance and other benefits that are broadly available to Parametric employees. Stock-based compensation awards and adjustments in base salary and bonuses are typically paid and/or put into effect at or shortly after , the firm’s fiscal year-end , October 31 ..

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Parametric’s Method to Determine Compensation

Parametric seeks to compensate portfolio managers commensurate with their responsibilities and performance, and competitive with other firms within the investment management industry. Salaries, bonuses and stock-based compensation are also influenced by the operating performance of Parametric and EVC .. Cash bonuses are determined primarily based on individual and Parametric performance. Stock-based compensation awards are similarly linked to performance, and may include EVC restricted stock, EVC stock options and Parametric equity awards. While the salaries of Parametric portfolio managers are comparatively fixed, cash bonuses and stock-based compensation may fluctuate from year to year, based on changes in individual and Parametric performance and other factors.

Code of Ethics

The Adviser, the Sub-Adviser and the Fund have adopted Codes of Ethics governing personal securities transactions pursuant to Rule 17j-1 under the 1940 Act. Under the Codes , employees of the Adviser and the Sub-Adviser may purchase and sell securities (including securities held or eligible for purchase by the Fund) subject to the provisions of the Codes and certain employees are also subject to pre-clearance, reporting requirements and /or other procedures.

The Codes of Ethics can be reviewed and copied at the Securities and Exchange Commission’s public reference room in Washington, DC (call 1-202- 551 -8090 for information on the operation of the public reference room); on the EDGAR Database on the SEC’s Internet site (http://www.sec.gov); or, upon payment of copying fees, by writing the SEC’s public reference section, Washington, DC 20549- 1520 , or by electronic mail at publicinfo@sec.gov.

Investment Advisory Services

Under the general supervision of the Fund’s Board, Eaton Vance will carry out the investment and reinvestment of all or a portion of the assets of the Fund, will furnish continuously an investment program with respect to the Fund, will determine which securities should be purchased, sold or exchanged, and will implement such determinations and will supervise the overall activities of the Sub-Adviser. Eaton Vance will furnish to the Fund investment advice and provide related office facilities and personnel for servicing the investments of the Fund. Eaton Vance will compensate all Trustees and officers of the Fund who are members of the Eaton Vance organization and who render investment services to the Fund, and will also compensate all other Eaton Vance personnel who provide research and investment services to the Fund.

Administrative Services

Under the Administration Agreement, Eaton Vance is responsible for managing the business affairs of the Fund, subject to the supervision of the Fund’s Board. Eaton Vance will furnish to the Fund all office facilities, equipment and personnel for administering the affairs of the Fund. Eaton Vance will compensate all Trustees and officers of the Fund who are members of the Eaton Vance organization and who render executive and administrative services to the Fund, and will also compensate all other Eaton Vance personnel who perform management and administrative services for the Fund. Eaton Vance’s administrative services include recordkeeping, preparation and filing of documents required to comply with federal and state securities laws, supervising the activities of the Fund’s custodian and transfer agent, providing assistance in connection with the Trustees’ and shareholders’ meetings, providing services in connection with repurchase offers, if any, and other administrative services necessary to conduct the Fund’s business.

CFTC Registration

Effective December 31, 2012, the Commodity Futures Trading Commission (“CFTC”) adopted certain regulatory changes that subject registered investment companies and advisers to regulation by the CFTC if a fund invests more than a prescribed level of its assets in certain CFTC-regulated instruments (including futures, certain options and swaps agreements) or markets itself as providing investment exposure to such instruments. The Fund has claimed an exclusion from the definition of the term “commodity pool operator” under the Commodity Exchange Act. Accordingly, neither the Fund nor the adviser with respect to the operation of the Fund is subject to CFTC regulation. Because of its management of other strategies, Eaton Vance is registered with the CFTC as a commodity pool operator. Eaton Vance is also registered as a commodity trading advisor. The CFTC has neither reviewed nor approved the Fund’s investment strategies or this Statement of Additional Information.

DETERMINATION OF NET ASSET VALUE

The net asset value of the Fund is determined by State Street Bank and Trust Company (as agent and custodian) by subtracting the liabilities of the Fund from the value of its total assets. The Fund is closed for business and will not issue a net asset value on the following business holidays and any other business day that the New York Stock Exchange (the “Exchange”) is closed: New Year’s Day, Martin Luther King, Jr. Day, Presidents’ Day, Good Friday, Memorial Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day.

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The Board has approved procedures pursuant to which investments are valued for purposes of determining the Fund’s net asset value. Listed below is a summary of the methods generally used to value investments (some or all of which may be held by the Fund ) under the procedures.

Equity securities (including common stock, exchange-traded funds, closed end funds, preferred equity securities, exchange-traded notes and other instruments that trade on recognized stock exchanges) are valued at the last sale, official close or if there are no reported sales at the mean between the bid and asked price on the primary exchange on which they are traded.

Most debt obligations are valued on the basis of market valuations furnished by a pricing service or at the mean of the bid and asked prices provided by recognized broker/dealers of such securities. The pricing service may use a pricing matrix to determine valuation.

Short-term instruments with remaining maturities of less than 397 days are valued on the basis of market valuations furnished by a pricing service or based on dealer quotations ..

Foreign securities and currencies are valued in U.S. dollars based on foreign currency exchange quotations supplied by a pricing service.

Senior and Junior Loans are valued on the basis of prices furnished by a pricing service. The pricing service uses transactions and market quotations from brokers in determining values.

Futures contracts are valued at the settlement or closing price on the primary exchange or board of trade on which they are traded.

Exchange-traded options are valued at the mean of the bid and asked prices. Over-the-counter options are valued based on quotations obtained from a pricing service or from a broker (typically the counterparty to the option).

Non-exchange traded derivatives (including swap agreements , forward contracts and equity participation notes) are generally valued on the basis of valuations provided by a pricing service or using quotes provided by a broker/dealer (typically the counterparty).

Precious metals are valued are valued at the New York Composite mean quotation.

Liabilities with a payment or maturity date of 364 days or less are stated at their principal value and longer dated liabilities generally will be carried at their fair value.

Valuations of foreign equity securities and total return swaps and exchange-traded futures contracts on non-North American equity indices may be adjusted from prices in effect at the close of trading on foreign exchanges to more accurately reflect their fair value as of the close of regular trading on the Exchange. Such fair valuations may be based on information provided by a pricing service.

Investments which are unable to be valued in accordance with the foregoing methodologies are valued at fair value using methods determined in good faith by or at the direction of the members of the Board. Such methods may include consideration of relevant factors, including but not limited to (i) the type of security, the existence of any contractual restrictions on the security’s disposition, (ii) the price and extent of public trading in similar securities of the issuer or of comparable companies or entities, (iii) quotations or relevant information obtained from broker-dealers or other market participants, (iv) information obtained from the issuer, analysts, and/or the appropriate stock exchange (for exchange-traded securities), (v) an analysis of the company’s or entity’s financial condition, (vi) an evaluation of the forces that influence the issuer and the market(s) in which the security is purchased and sold (vii) an analysis of the terms of any transaction involving the issuer of such securities; and (viii) any other factors deemed relevant by the investment adviser. The portfolio managers of one Eaton Vance fund that invests in Senior and Junior Loans may not possess the same information about a Senior or Junior Loan as the portfolio managers of another Eaton Vance fund. As such, at times the fair value of a Loan determined by certain Eaton Vance portfolio managers may vary from the fair value of the same Loan determined by other portfolio managers.

PORTFOLIO TRADING

Decisions concerning the execution of portfolio security transactions, including the selection of the market and the executing firm, are made by Eaton Vance, the Fund’s Adviser, or Parametric as the Fund’s Sub-Adviser. As used below, “Adviser” refers to Eaton Vance and Parametric, as applicable. The Fund is responsible for the expenses associated with its portfolio transactions. The Adviser is also responsible for the execution of transactions for all other accounts managed by it. The Adviser places the portfolio security transactions for execution with one or more broker-dealer firms. The Adviser uses its best efforts to obtain execution of portfolio security transactions at prices which in the Adviser’s judgment are advantageous to the client and at reasonably competitive spreads or (when a disclosed commission is being charged) at reasonably competitive commission rates. In seeking such execution, the Adviser will use its best judgment in evaluating the terms of a transaction, and will give consideration to various relevant factors, including without limitation the full range and quality of the broker-dealer firm’s services including the

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responsiveness of the firm to the Adviser, the size and type of the transaction, the nature and character of the market for the security, the confidentiality, speed and certainty of effective execution required for the transaction, the general execution and operational capabilities of the broker-dealer firm, the reputation, reliability, experience and financial condition of the firm, the value and quality of the services rendered by the firm in other transactions, and the amount of the spread or commission, if any. In addition, the Adviser may consider the receipt of Research Services (as defined below), provided it does not compromise the adviser’s obligation to seek best overall execution for the Fund and is otherwise in compliance with applicable law. The Adviser may engage in portfolio brokerage transactions with a broker-dealer firm that sells shares of Eaton Vance funds, provided such transactions are not directed to that firm as compensation for the promotion or sale of such shares.

Transactions on stock exchanges and other agency transactions involve the payment of negotiated brokerage commissions. Such commissions vary among different broker-dealer firms, and a particular broker-dealer may charge different commissions according to such factors as the difficulty and size of the transaction and the volume of business done with such broker-dealer. Transactions in foreign securities often involve the payment of brokerage commissions, which may be higher than those in the United States. There is generally no stated commission in the case of securities traded in the over-the-counter markets including transactions in fixed-income securities which are generally purchased and sold on a net basis (i.e., without commission) through broker-dealers and banks acting for their own account rather than as brokers. Such firms attempt to profit from such transactions by buying at the bid price and selling at the higher asked price of the market for such obligations, and the difference between the bid and asked price is customarily referred to as the spread. Fixed-income transactions may also be transactions directly with the issuer of the obligations. In an underwritten offering the price paid often includes a disclosed fixed commission or discount retained by the underwriter or dealer. Although spreads or commissions paid on portfolio security transactions will, in the judgment of the investment adviser, be reasonable in relation to the value of the services provided, commissions exceeding those which another firm might charge may be paid to broker-dealers who were selected to execute transactions on behalf of the investment adviser’s clients in part for providing brokerage and research services to the investment adviser as permitted by applicable law. Pursuant to the safeharbor provided in Section 28(e) of the Securities Exchange Act of 1934, as amended (the “1934 Act”), and to the extent permitted by other applicable law, a broker or dealer who executes a portfolio transaction on behalf of the investment adviser client may receive a commission which is in excess of the amount of commission another broker or dealer would have charged for effecting that transaction if the investment adviser determines in good faith that such compensation was reasonable in relation to the value of the brokerage and research services provided. This determination may be made on the basis of either that particular transaction or on the basis of the overall responsibility which the investment adviser and its affiliates have for accounts over which they exercise investment discretion. “Research Services” as used herein includes any and all brokerage and research services to the extent permitted by Section 28(e) and other applicable law. Generally, Research Services may include, but are not limited to, such matters as research, analytical and quotation services, data, information and other services products and materials which assist the investment adviser in the performance of its investment responsibilities. More specifically, Research Services may include general economic, political, business and market information, industry and company reviews, evaluations of securities and portfolio strategies and transactions, technical analysis of various aspects of the securities markets, recommendations as to the purchase and sale of securities and other portfolio transactions, certain financial, industry and trade publications, certain news and information services, and certain research oriented computer software, data bases and services. Any particular Research Service obtained through a broker-dealer may be used by the investment adviser in connection with client accounts other than those accounts which pay commissions to such broker-dealer, to the extent permitted by applicable law. Any such Research Service may be broadly useful and of value to the investment adviser in rendering investment advisory services to all or a significant portion of its clients, or may be relevant and useful for the management of only one client’s account or of a few clients’ accounts, or may be useful for the management of merely a segment of certain clients’ accounts, regardless of whether any such account or accounts paid commissions to the brokerdealer through which such Research Service was obtained. The investment adviser evaluates the nature and quality of the various Research Services obtained through broker-dealer firms and, to the extent permitted by applicable law, may attempt to allocate sufficient portfolio security transactions to such firms to ensure the continued receipt of Research Services which the investment adviser believes are useful or of value to it in rendering investment advisory services to its clients. The investment adviser may also receive brokerage and Research Services from underwriters and dealers in fixed-price offerings, when permitted by applicable law.

Research Services provided by (and produced by) broker-dealers that execute portfolio transactions or from affiliates of executing broker-dealers are referred to as “Proprietary Research”. Except for trades executed in jurisdictions where such considerations is not permissible, the investment adviser may and does consider the receipt of Proprietary Research Services as a factor in selecting broker - dealers to execute client portfolio transactions, provided it does not compromise the investment adviser’s obligation to seek best overall execution. In jurisdictions where permissible, the investment adviser also may consider the receipt of Research Services under so called “client commission arrangements” or “commission sharing arrangements” (both referred to as “CCAs”) as a factor in selecting broker dealers to execute transactions, provided it does not compromise the investment adviser’s obligation to seek best overall execution. Under a CCA arrangement, the investment adviser may cause client accounts

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to effect transactions through a broker-dealer and request that the broker-dealer allocate a portion of the commissions paid on those transactions to a pool of commission credits that are paid to other firms that provide Research Services to the investment adviser. Under a CCA, the broker-dealer that provides the Research Services need not execute the trade. Participating in CCAs may enable the investment adviser to consolidate payments for research using accumulated client commission credits from transactions executed through a particular broker-dealer to periodically pay for Research Services obtained from and provided by other firms, including other broker-dealers that supply Research Services. The investment adviser believes that CCAs offer the potential to optimize the execution of trades and the acquisition of a variety of high quality Research Services that the investment adviser might not be provided access to absent CCAs. The investment adviser will only enter into and utilize CCAs to the extent permitted by Section 28(e) and other applicable law.

Fund trades may implicate laws of the United Kingdom, including rules of the UK Financial Conduct Authority, which govern client trading commissions and Research Services (“UK Law”). Broadly speaking, under UK Law the investment adviser may not accept any good or service when executing an order unless that good or service either is directly related to the execution of trades on behalf of its clients/customers or amounts to the provision of substantive research (as defined under UK Law). These requirements may also apply with respect to orders in connection with which the investment adviser receives goods and services under a CCA or other bundled brokerage arrangement.

The investment companies sponsored by the investment adviser or its affiliates may also allocate brokerage commissions to acquire information relating to the performance, fees and expenses of such companies and other investment companies, which information is used by the Trustees of such companies to fulfill their responsibility to oversee the quality of the services provided to various entities, including the investment adviser, to such companies. Such companies may also pay cash for such information.

Securities considered as investments for the Fund may also be appropriate for other investment accounts managed by the investment adviser or its affiliates. Whenever decisions are made to buy or sell securities by the Fund and one or more of such other accounts simultaneously, the investment adviser will allocate the security transactions (including “new” issues) in a manner which it believes to be equitable under the circumstances. As a result of such allocations, there may be instances where the Fund will not participate in a transaction that is allocated among other accounts. If an aggregated order cannot be filled completely, allocations will generally be made on a pro rata basis. An order may not be allocated on a pro rata basis where, for example: (i) consideration is given to portfolio managers who have been instrumental in developing or negotiating a particular investment; (ii) consideration is given to an account with specialized investment policies that coincide with the particulars of a specific investment; (iii) pro rata allocation would result in odd-lot or de minimis amounts being allocated to a portfolio or other client; or (iv) where the investment adviser reasonably determines that departure from a pro rata allocation is advisable. While these aggregations and allocation policies could have a detrimental effect on the price or amount of the securities available to a Portfolio from time to time, it is the opinion of the members of the Board that the benefits from the investment adviser organization outweigh any disadvantage that may arise from exposure to simultaneous transactions.

The following table shows brokerage commissions paid during the fiscal years ended December 31, 2016, 2015 and 2014 as well as the amount of portfolio security transactions for the most recent fiscal year (if any) that were directed to firms that provided some Research Services to the investment adviser or its affiliates (see above), and the commissions paid in connection therewith.


Fiscal Year End	Brokerage Commission Paid	Amount of Transactions Directed to Firms Providing Research	Commissions Paid on Transactions Directed to Firms Providing Research
December 31, 2016	$53,528	$139,775,147	$45,769
December 31, 2015	$58,035
December 31, 2014	$72,419

During the fiscal year ended December 31, 2016 , the Fund held no securities of its “regular brokers or dealers”, as that term is defined in Rule 10b-1 of the 1940 Act ..

TAXES

The Fund intends to qualify each year as a regulated investment company (“RIC”) under the Code. Accordingly, the Fund intends to satisfy certain requirements relating to sources of its income and diversification of its assets and to distribute substantially all of its net income and net short-term and long-term capital gains (after reduction by any available capital loss carryforwards) in accordance with the timing requirements imposed by the Code, so as to maintain its RIC status and to avoid paying any federal income or excise tax. To the extent it qualifies for treatment as a RIC and satisfies the above-mentioned distribution

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requirements, the Fund will not be subject to federal income tax on income paid to its shareholders in the form of dividends or capital gain distributions.

The Fund must also satisfy certain requirements with respect to the diversification of its assets. The Fund must have, at the close of each quarter of its taxable year, at least 50% of the value of its total assets represented by cash and cash items, U.S. government securities, securities of other RICs, and other securities that, in respect of any one issuer, do not represent more than 5% of the value of the assets of the Fund or more than 10% of the voting securities of that issuer. In addition, at those times, not more than 25% of the value of the Fund’s assets may be invested in securities (other than U.S. Government securities or the securities of other RICs) of any one issuer, or of two or more issuers that the Fund controls and which are engaged in the same or similar trades or businesses or related trades or businesses, or of one or more qualified publicly traded partnerships. For purposes of asset diversification testing, obligations issued or guaranteed by certain agencies or instrumentalities of the U.S. government, such as the Federal Agricultural Mortgage Corporation, the Federal Farm Credit System Financial Assistance Corporation, Federal Home Loan Banks, Federal Home Loan Mortgage Corporation, Federal National Mortgage Association, Government National Mortgage Association, and Student Loan Marketing Corporation are treated as U.S. government securities.

The Fund also seeks to avoid the imposition of a federal excise tax on its ordinary income and capital gain net income .. However, if the Fund fails to distribute in a calendar year substantially all of its ordinary income for such year and substantially all of its capital gain net income for the one-year period ending October 31 (or later if the Fund is permitted so to elect and so elects), plus any retained amount from the prior year, the Fund will be subject to a 4% excise tax on the undistributed amounts. In order to avoid incurring a federal excise tax obligation, the Code requires that a RIC distribute (or be deemed to have distributed) by December 31 of each calendar year (i) at least 98% of its ordinary income (not including tax-exempt income) for such year, (ii) at least 98.2% of its capital gain net income (which is the excess of its realized capital gains over its realized capital losses), generally computed on the basis of the one-year period ending on October 31 of such year, after reduction by any available capital loss carryforwards and (iii) 100% of any income and capital gains from the prior year (as previously computed) that were not distributed during such year and on which the Fund paid no federal income tax. If the Fund fails to meet these requirements it will be subject to a nondeductible 4% excise tax on the undistributed amounts. For the foregoing purposes, a RIC is treated as having distributed any amount on which it is subject to income tax for any tax year ending in such calendar year and, if it so elects, the amounts on which qualified estimated tax payments are made by it during such calendar year (in which case the amount it is treated as having distributed in the following calendar year will be reduced.)If the Fund does not qualify as a RIC for any taxable year, the Fund’s taxable income will be subject to corporate income taxes, and all distributions from earnings and profits, including distributions of net capital gain (if any), will be taxable to the shareholder as ordinary income. Such distributions will be treated as qualified dividend income with respect to shareholders who are individuals and will be eligible for the dividends received deduction (“DRD”) in the case of shareholders taxed as corporations. In order to requalify for taxation as a RIC, the Fund may be required to recognize unrealized gains, pay substantial taxes and interest, and make substantial distributions.

For U.S. federal income tax purposes, distributions paid out of the Fund’s current or accumulated earnings and profits will, except in the case of distributions of qualified dividend income and capital gain dividends described below, be taxable as ordinary dividend income. Certain income distributions paid by the Fund (whether paid in cash or reinvested in additional Fund shares) to individual taxpayers are taxed at rates applicable to net long-term capital gains (20%, 15%, or 0%, depending on an individual’s tax bracket). This tax treatment applies only if certain holding period requirements and other requirements are satisfied by the shareholder and the dividends are attributable to qualified dividend income received by the Fund itself. For this purpose, “qualified dividend income” means dividends received by the Fund from United States corporations and “qualified foreign corporations,” provided that the Fund satisfies certain holding period and other requirements in respect of the stock of such corporations. There can be no assurance as to what portion of the Fund’s dividend distributions will qualify for favorable treatment.

Shareholders receiving any distribution from the Fund in the form of additional shares pursuant to the dividend reinvestment plan will be treated as receiving a taxable distribution in an amount equal to the fair market value of the shares received, determined as of the reinvestment date.

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Dividends of investment company taxable income designated by the Fund and received by corporate shareholders of the Fund will qualify for the DRD to the extent of the amount of qualifying dividends received by the Fund from domestic corporations for the taxable year. A dividend received by the Fund will not be treated as a qualifying dividend (i) if the stock on which the dividend is paid is considered to be “debt-financed” (generally, acquired with borrowed funds), (ii) if the Fund fails to meet certain holding period requirements for the stock on which the dividend is paid or (iii) to the extent that the Fund is under an obligation (pursuant to a short sale or otherwise) to make related payments with respect to positions in substantially similar or related property. Moreover, the DRD may be disallowed or reduced if the corporate shareholder fails to satisfy the foregoing requirements with respect to its shares of the Fund or by application of the Code.

Distributions of net capital gain, if any, designated as capital gains dividends are taxable to a shareholder as long-term capital gains, regardless of how long the shareholder has held Fund shares. A distribution of an amount in excess of the Fund’s current and accumulated earnings and profits will be treated by a shareholder as a return of capital which is applied against and reduces the shareholder’s basis in his or her shares. To the extent that the amount of any such distribution exceeds the shareholder’s basis in his or her shares, the excess will be treated by the shareholder as gain from a sale or exchange of the shares. Distributions of gains from the sale of investments that the Fund owned for one year or less will be taxable as ordinary income.

The Fund may elect to retain its net capital gain or a portion thereof for investment and be taxed at corporate rates on the amount retained. In such case, it may designate the retained amount as undistributed capital gains in a notice to its shareholders who will be treated as if each received a distribution of his pro rata share of such gain, with the result that each shareholder will (i) be required to report his pro rata share of such gain on his tax return as long-term capital gain, (ii) receive a refundable tax credit for his pro rata share of tax paid by the Fund on the gain and (iii) increase the tax basis for his shares by an amount equal to the deemed distribution less the tax credit.

Selling shareholders will generally recognize gain or loss in an amount equal to the difference between the shareholder’s adjusted tax basis in the shares sold and the sale proceeds. If the shares are held as a capital asset, the gain or loss will be a capital gain or loss. The maximum tax rate applicable to net capital gains recognized by individuals and other non-corporate taxpayers is (i) the same as the maximum ordinary income tax rate for gains recognized on the sale of capital assets held for one year or less, or (ii) 20% for gains recognized on the sale of capital assets held for more than one year (as well as certain capital gain distributions ) ( 15% or 0% for individuals in certain tax brackets).

Any loss realized upon the sale or exchange of Fund shares with a holding period of six months or less will be treated as a long-term capital loss to the extent of any capital gain distributions received with respect to such shares. In addition, all or a portion of a loss realized on a sale or other disposition of Fund shares may be disallowed under “wash sale” rules to the extent the shareholder acquires other shares of the same Fund (whether through the reinvestment of distributions or otherwise) within a period of 61 days beginning 30 days before and ending 30 days after the date of disposition of the common shares. Any disallowed loss will result in an adjustment to the shareholder’s tax basis in some or all of the other shares acquired.

Sales charges paid upon a purchase of shares cannot be taken into account for purposes of determining gain or loss on a sale of the shares before the 91st day after their purchase to the extent a sales charge is reduced or eliminated in a subsequent acquisition of shares of the Fund (or of another fund), during the period beginning on the date of such sale and ending on January 31 of the calendar year following the calendar year in which the sale was made, pursuant to the reinvestment or exchange privilege. Any disregarded amounts will result in an adjustment to the shareholder’s tax basis in some or all of any other shares acquired.

Dividends and distributions on the Fund’s shares are generally subject to federal income tax as described herein to the extent they do not exceed the Fund’s realized income and gains, even though such dividends and distributions may economically represent a return of a particular shareholder’s investment. Such distributions are likely to occur in respect of shares purchased at a time when the Fund’s net asset value reflects gains that are either unrealized, or realized but not distributed. Such realized gains may be required to be distributed even when the Fund’s net asset value also reflects unrealized losses. Certain distributions declared in October, November or December and paid in the following January will be taxed to shareholders as if received on December 31 of the year in which they were declared. In addition, certain other distributions made after the close of a taxable year of the Fund may be “spilled back” and treated as paid by the Fund (except for purposes of the non-deductible 4% federal excise tax) during such taxable year. In such case, shareholders will be treated as having received such dividends in the taxable year in which the distributions were actually made.

The Fund will inform shareholders of the source and tax status of all distributions promptly after the close of each calendar year.

The benefits of the reduced tax rates applicable to long-term capital gains and qualified dividend income may be impacted by the application of the alternative minimum tax to individual shareholders.

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In the case of Fund transactions involving S&P 500 call options (or other listed options on broad-based securities indices), Code Section 1256 generally will require any gain or loss arising from the lapse, closing out or exercise of such positions to be treated as 60% long-term and 40% short-term capital gain or loss. In addition, the Fund generally will be required to “mark to market” (i.e., treat as sold for fair market value) each such outstanding position which it holds on October 31 or at the close of each taxable year. If a Section 1256 Contract held by the Fund at the end of a taxable year is sold in the following year, the amount of any gain or loss realized on such sale will be adjusted to reflect the gain or loss previously taken into account under the “mark to market” rules. In addition to most index call options, Section 1256 Contracts include certain other options contracts, certain regulated futures contracts, and certain other financial contracts.

The Code allows a taxpayer to elect to offset gains and losses from positions that are part of a “mixed straddle.” A “mixed straddle” is any straddle in which one or more but not all positions are Section 1256 Contracts. The Fund may be eligible to elect to establish one or more mixed straddle accounts for certain of its mixed straddle trading positions. The mixed straddle account rules require a daily “marking to market” of all open positions in the account and a daily netting of gains and losses from all positions in the account. At the end of a taxable year, the annual net gains or losses from the mixed straddle account are recognized for tax purposes. The net capital gain or loss is treated as 60% long-term and 40% short-term capital gain or loss if attributable to the Section 1256 Contract positions, or all short-term capital gain or loss if attributable to the non-Section 1256 Contract positions.

The Fund may recognize gain (but not loss) from a constructive sale of certain “appreciated financial positions” if the Fund enters into a short sale, offsetting notional principal contract, or forward contract transaction with respect to the appreciated position or substantially identical property. Appreciated financial positions subject to this constructive sale treatment include interests (including options and forward contracts and short sales) in stock and certain other instruments. Constructive sale treatment does not apply if the transaction is closed out not later than thirty days after the end of the taxable year in which the transaction was initiated, and the underlying appreciated securities position is held unhedged for at least the next sixty days after the hedging transaction is closed.

Gain or loss from a short sale of property is generally considered as capital gain or loss to the extent the property used to close the short sale constitutes a capital asset in the Fund’s hands. Except with respect to certain situations where the property used to close a short sale has a long-term holding period on the date the short sale is entered into, gains on short sales generally are short-term capital gains. A loss on a short sale will be treated as a long-term capital loss if, on the date of the short sale, “substantially identical property” has been held by the Fund for more than one year. In addition, these rules may also terminate the running of the holding period of “substantially identical property” held by the Fund.

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The Fund’s transactions in futures contracts and options will be subject to special provisions of the Code that, among other things, may affect the character of gains and losses realized by the Fund (i.e., may affect whether gains or losses are ordinary or capital, or short-term or long-term), may accelerate recognition of income to the Fund and may defer Fund losses. These rules could, therefore, affect the character, amount and timing of distributions to shareholders. These provisions also (a) will require the Fund to mark-to-market certain types of the positions in its portfolio (i.e., treat them as if they were closed out), and (b) may cause the Fund to recognize income without receiving cash with which to make distributions in amounts necessary to satisfy the 90% distribution requirement for qualifying to be taxed as a RIC and the 98% and 98.2% distribution requirements for avoiding excise taxes. The Fund will monitor its transactions, will make the appropriate tax elections and will make the appropriate entries in its books and records when it acquires any futures contract, option or hedged investment in order to mitigate the effect of these rules and prevent disqualification of the Fund from being taxed as a regulated investment company.

Further, certain of the Fund’s investment practices are subject to special and complex federal income tax provisions that may, among other things, (i) convert dividends that would otherwise constitute qualified dividend income into short-term capital gain or ordinary income taxed at the higher rate applicable to ordinary income, (ii) treat dividends that would otherwise be eligible for the corporate dividends received deduction as ineligible for such treatment, (iii) disallow, suspend or otherwise limit the allowance of certain losses or deductions, (iv) convert long-term capital gain into short-term capital gain or ordinary income, (v) convert an ordinary loss or deduction into a capital loss (the deductibility of which is more limited) and (vi) cause the Fund to recognize income or gain without a corresponding receipt of cash; (vii) adversely affect the time as to when a purchase or sale of stock or securities is deemed to occur, (viii) adversely alter the characterization of certain complex financial transactions, and (ix) produce income that will not qualify as good income for purposes of the 90% annual gross income requirement described above.

Dividends and interest received, and gains realized, by the Fund on foreign securities may be subject to income, withholding or other taxes imposed by foreign countries and U.S. possessions (collectively “foreign taxes”) that would reduce the return on its securities. Tax conventions between certain countries and the United States, however, may reduce or eliminate foreign taxes, and many foreign countries do not impose taxes on capital gains in respect of investments by foreign investors. Shareholders will generally not be entitled to claim a credit or deduction with respect to foreign taxes paid by the Fund.

The Fund may invest in the stock of “passive foreign investment companies” (“PFICs”). A PFIC is any foreign corporation (with certain exceptions) that, in general, meets either of the following tests: (1) at least 75% of its gross income is passive or (2) an average of at least 50% of its assets produce, or are held for the production of, passive income. Under certain circumstances, the Fund will be subject to federal income tax on a portion of any “excess distribution” received on the stock of a PFIC or of any gain from disposition of that stock (collectively “PFIC income”), plus interest thereon, even if the Fund distributes the PFIC income as a taxable dividend to its shareholders. The balance of the PFIC income will be included in the Fund’s investment company taxable income and, accordingly, will not be taxable to it to the extent it distributes that income to its shareholders.

If the Fund invests in a PFIC and elects to treat the PFIC as a “qualified electing fund” (“QEF”), then in lieu of the foregoing tax and interest obligation, the Fund will be required to include in income each year its pro rata share of the QEF’s annual ordinary earnings and net capital gain -- which it may have to distribute to satisfy the distribution requirement and avoid imposition of the excise tax -- even if the QEF does not distribute those earnings and gain to the Fund. In most instances it will be very difficult, if not impossible, to make this election because of certain of its requirements.

The Fund may elect to “mark to market” its stock in any PFIC. “Marking-to-market,” in this context, means including in ordinary income each taxable year the excess, if any, of the fair market value of a PFIC’s stock over the Fund’s adjusted basis therein as of the end of that year. Pursuant to the election, the Fund also would be allowed to deduct (as an ordinary, not capital, loss) the excess, if any, of its adjusted basis in PFIC stock over the fair market value thereof as of the taxable year-end, but only to the extent of any net mark-to-market gains (reduced by any prior deductions) with respect to that stock included by the Fund for prior taxable years under the election. The Fund’s adjusted basis in each PFIC’s stock with respect to which it has made this election will be adjusted to reflect the amounts of income included and deductions taken thereunder.

Under Section 988 of the Code, gains or losses attributable to fluctuations in exchange rates between the time the Fund accrues income or receivables or expenses or other liabilities denominated in a foreign currency and the time the Fund actually collects such income or receivables or pays such liabilities are generally treated as ordinary income or loss.

Amounts paid by the Fund to individuals and certain other shareholders who have not provided the Fund with their correct taxpayer identification number (“TIN”) and certain certifications required by the Service as well as shareholders with respect to whom the Fund has received certain information from the Service or a broker may be subject to “backup” withholding of federal income tax arising from the Fund’s taxable dividends and other distributions as well as the gross proceeds of sales of shares, at a rate of 28%. An individual’s TIN is generally his or her social security number. Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from payments made to a shareholder may be refunded or credited against such shareholder’s federal income tax liability, if any, provided that the required information is furnished to the Service.

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Properly reported dividends are generally exempt from U.S. federal withholding tax where they (i) are paid in respect of the Fund’s “qualified net interest income” (generally, the Fund’s U.S. source interest income, other than certain contingent interest and interest from obligations of a corporation or partnership in which the Fund is at least a 10% shareholder, reduced by expenses that are allocable to such income) or (ii) are paid in respect of the Fund’s “qualified short-term capital gains” (generally, the excess of the Fund’s net short-term capital gain over the Fund’s long-term capital loss for such taxable year). However, depending on its circumstances, the Fund may report all, some or none of its potentially eligible dividends as such qualified net interest income or as qualified short-term capital gains and/or treat such dividends, in whole or in part, as ineligible for this exemption from withholding. In order to qualify for this exemption from withholding, a non-U.S. shareholder would need to comply with applicable certification requirements relating to its non-U.S. status (including, in general, furnishing an IRS Form W-8BEN, IRS Form W-8BEN-E, or substitute Form). In the case of shares held through an intermediary, the intermediary could withhold even if the Fund designates the payment as qualified net interest income or qualified short-term capital gain. Non-U.S. shareholders should contact their intermediaries with respect to the application of these rules to their accounts.

Compliance with FATCA. A 30% withholding tax is imposed on U.S.-source dividends, including those paid by the Fund and, after December 31, 2018, will be imposed on gross proceeds from the sale of property producing U.S.-source dividends, including interests in the Fund, to (i) foreign financial institutions including non-U.S. investment funds and foreign financial institutions acting as intermediaries unless they agree to collect and disclose to the IRS information regarding their direct and indirect U.S. account holders and (ii) certain other foreign entities, unless they certify certain information regarding their direct and indirect U.S. owners. If a payment by the Fund is subject to withholding under FATCA, the Fund is required to withhold even if such payment would otherwise be exempt from withholding under the rules applicable to foreign shareholders described above (e.g., short-term capital gain dividends and dividends attributable to qualified net interest income). To avoid withholding, foreign financial institutions will need to either enter into agreements with the IRS that state that they will provide the IRS information, including the names, addresses and taxpayer identification numbers of direct and indirect U.S. account holders, comply with due diligence procedures with respect to the identification of U.S. accounts, report to the IRS certain information with respect to U.S. accounts maintained, agree to withhold tax on certain payments made to non-compliant foreign financial institutions or to account holders who fail to provide the required information, and determine certain other information as to their account holders or, in the event that an applicable intergovernmental agreement and implementing legislation are adopted, agree to provide certain information to other revenue authorities for transmittal to the IRS. Other foreign entities will need to either provide the name, address, and taxpayer identification number of each substantial U.S. owner or certifications of no substantial U.S. ownership unless certain exceptions apply or agree to provide certain information to other revenue authorities for transmittal to the IRS. Shareholders should consult their own tax advisors regarding the possible implications of these requirements on their investment in the Fund.

The foregoing briefly summarizes some of the important federal income tax consequences to Common Shareholders of investing in Common Shares, reflects the federal tax law as of the date of this Statement of Additional Information, and does not address special tax rules applicable to certain types of investors, such as corporate and foreign investors. Unless otherwise noted, this discussion assumes that an investor is a U.S. person and holds Common Shares as a capital asset. This discussion is based upon current provisions of the Code, the regulations promulgated thereunder, and judicial and administrative ruling authorities, all of which are subject to change or differing interpretations by the courts or the IRS retroactively or prospectively. Investors should consult their tax advisors regarding other federal, state or local tax considerations that may be applicable in their particular circumstances, as well as any proposed tax law changes.

State and local taxes

Shareholders should consult their own tax advisors as the state or local tax consequences of investing in the Fund.

OTHER INFORMATION

The Fund is an organization of the type commonly known as a “Massachusetts business trust.” Under Massachusetts law, shareholders of such a trust may, in certain circumstances, be held personally liable as partners for the obligations of the trust. The Declaration of Trust contains an express disclaimer of shareholder liability in connection with Fund property or the acts, obligations or affairs of the Fund. The Declaration of Trust, in coordination with the Fund’s By-laws, also provides for indemnification out of Fund property of any shareholder held personally liable for the claims and liabilities to which a shareholder may become subject by reason of being or having been a shareholder. Thus, the risk of a shareholder incurring financial loss on account of shareholder liability is limited to circumstances in which the Fund itself is unable to meet its obligations. The Fund has been advised by its counsel that the risk of any shareholder incurring any liability for the obligations of the Fund is remote.

The Declaration of Trust provides that the Trustees will not be liable for errors of judgment or mistakes of fact or law; but nothing in the Declaration of Trust protects a Trustee against any liability to the Fund or its shareholders to which he or she would otherwise be subject by reason of willful misfeasance, bad faith, gross negligence, or reckless disregard of the duties involved in

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the conduct of his or her office. Voting rights are not cumulative, which means that the holders of more than 50% of the shares voting for the election of Trustees can elect 100% of the Trustees and, in such event, the holders of the remaining less than 50% of the shares voting on the matter will not be able to elect any Trustees.

The Declaration of Trust provides that no person shall serve as a Trustee if shareholders holding two-thirds of the outstanding shares have removed him from that office either by a written declaration filed with the Fund’s custodian or by votes cast at a meeting called for that purpose. The Declaration of Trust further provides that the Trustees of the Fund shall promptly call a meeting of the shareholders for the purpose of voting upon a question of removal of any such Trustee or Trustees when requested in writing to do so by the record holders of not less than 10 per centum of the outstanding shares.

The Fund’s Prospectus, any related Prospectus Supplement and this SAI do not contain all of the information set forth in the Registration Statement that the Fund has filed with the SEC. The complete Registration Statement may be obtained from the SEC upon payment of the fee prescribed by its Rules and Regulations.

CUSTODIAN

INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

FINANCIAL STATEMENTS

The audited financial statements and the report of the independent registered public accounting firm of the Fund for the fiscal year ended December 31, 2016 are incorporated herein by reference from the Fund’s most recent Annual Report to Common Shareholders filed with the SEC (Accession No. 0001193125- 17-059204 ) on Form N-CSR pursuant to Rule 30b2-1 under the 1940 Act.

Deloitte & Touche LLP (“D&T”), the Fund’s principal accountant, has informed the Audit Committee that certain relationships between D&T and its affiliates (“Deloitte Entities”) and one or more lenders who are record owners of more than 10% of the shares of one or more funds within the Eaton Vance family of funds implicate Rule 2-01(c)(1)(ii)(A) of Regulation S-X (the “Loan Rule”), calling into question D&T’s independence with respect to the Eaton Vance family of funds. The Loan Rule prohibits an accounting firm, such as D&T, from having certain financial relationships with its audit clients and affiliated entities. Specifically, the Loan Rule provides, in relevant part, that an accounting firm generally would not be independent if it or a “covered person” of the accounting firm (within the meaning of applicable SEC rules relating to auditor independence) receives a loan from a lender that is a “record or beneficial owner of more than ten percent of the audit client’s equity securities.” The Fund is providing this disclosure to explain the facts and circumstances as well as D&T’s conclusions concerning D&T’s objectivity and impartiality with respect to the audits of the Fund notwithstanding the existence of one or more breaches of the Loan Rule.

On June 20, 2016, the SEC issued no-action relief to another mutual fund complex (see Fidelity Management & Research Company et al., No-Action Letter (June 20, 2016) (the “No-Action Letter”)) related to an auditor independence issue arising under the Loan Rule. In the No-Action Letter, the SEC indicated that it would not recommend enforcement action against the fund group if the auditor is not in compliance with the Loan Rule provided that: (1) the auditor has complied with PCAOB Rule 3526(b)(1) and 3526(b)(2); (2) the auditor’s non-compliance under the Loan Rule is with respect to certain lending relationships; and (3) notwithstanding such non-compliance, the auditor has concluded that it is objective and impartial with respect to the issues encompassed within its engagement as auditor of the funds. The SEC has indicated that the no-action relief will expire 18 months from its issuance.

Based on information provided by D&T to the Audit Committee, the requirements of the No-Action Letter appear to be met with respect to D&T’s lending relationships described above. Among other things, D&T has advised the Audit Committee of its conclusion that the consequences of the breach of the Loan Rule have been satisfactorily addressed, that D&T’s objectivity and impartiality in the planning and conduct of the audits of the Fund’s financial statements has not been compromised and that, notwithstanding the breach, D&T is in a position to continue as the auditor for the Funds and D&T does not believe any actions need to be taken with respect to previously issued reports by D&T. D&T has advised the Audit Committee that these conclusions were based in part on its consideration of the No-Action Letter and other relevant information communicated to the Audit Committee.

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APPENDIX A

Eaton Vance Funds

Proxy Voting Policy and Procedures

I. Overview

The Boards of Trustees (the “Board”) of the Eaton Vance Funds¹ have determined that it is in the interests of the Funds’ shareholders to adopt these written proxy voting policy and procedures (the “Policy”). For purposes of this Policy:

•

“Fund” means each registered investment company sponsored by the Eaton Vance organization; and

•

“Adviser” means the adviser or sub-adviser responsible for the day-to-day management of all or a portion of the Fund’s assets.

II. Delegation of Proxy Voting Responsibilities

The Board hereby delegates to the Adviser responsibility for voting the Fund’s proxies as described in this Policy. In this connection, the Adviser is required to provide the Board with a copy of its proxy voting policies and procedures (“Adviser Procedures”) and all Fund proxies will be voted in accordance with the Adviser Procedures, provided that in the event a material conflict of interest arises with respect to a proxy to be voted for the Fund (as described in Section IV below) the Adviser shall follow the process for voting such proxy as described in Section IV below.

The Adviser is required to report any material change to the Adviser Procedures to the Board in the manner set forth in Section V below. In addition, the Board will review the Adviser Procedures annually.

III. Delegation of Proxy Voting Disclosure Responsibilities

Pursuant to Rule 30b1-4 promulgated under the Investment Company Act of 1940, as amended (the “1940 Act”), the Fund is required to file Form N-PX no later than August 31st of each year. On Form N-PX, the Fund is required to disclose, among other things, information concerning proxies relating to the Fund’s portfolio investments, whether or not the Fund (or its Adviser) voted the proxies relating to securities held by the Fund and how it voted on the matter and whether it voted for or against management.

To facilitate the filing of Form N-PX for the Fund:

•

The Adviser is required to record, compile and transmit in a timely manner all data required to be filed on Form N-PX for the Fund that it manages. Such data shall be transmitted to Eaton Vance Management, which acts as administrator to the Fund (the “Administrator”) or the third party service provider designated by the Administrator; and

•

the Administrator is required to file Form N-PX on behalf of the Fund with the Securities and Exchange Commission (“Commission”) as required by the 1940 Act. The Administrator may delegate the filing to a third party service party provided each such filing is reviewed and approved by the Administrator.

IV. Conflicts of Interest

The Board expects the Adviser, as a fiduciary to the Fund it manages, to put the interests of the Fund and its shareholders above those of the Adviser. When required to vote a proxy for the Fund, the Adviser may have material business relationships with the issuer soliciting the proxy that could give rise to a potential material conflict of interest for the Adviser.² In the event such a material conflict of interest arises, the Adviser, to the extent it is aware or reasonably should have been aware of the material conflict, will refrain from voting any proxies related to companies giving rise to such material conflict until it notifies and consults with the appropriate Board, or any committee, sub-committee or group of Independent Trustees identified by the Board (as long as such committee, sub-committee or group contains at least two or more Independent Trustees) (the “Board Members”), concerning the material conflict.³ For ease of communicating with the Board Members, the Adviser is required to provide the foregoing notice to the Fund’s Chief Legal Officer who will then notify and facilitate a consultation with the Board Members.

Once the Board Members have been notified of the material conflict:

•

They shall convene a meeting to review and consider all relevant materials related to the proxies involved. This meeting shall be convened within 3 business days, provided that it an effort will be made to convene the meeting sooner if the proxy must be voted in less than 3 business days;

•

In considering such proxies, the Adviser shall make available all materials requested by the Board Members and make reasonably available appropriate personnel to discuss the matter upon request.

•

The Board Members will then instruct the Adviser on the appropriate course of action with respect to the proxy at issue.

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If the Board Members are unable to meet and the failure to vote a proxy would have a material adverse impact on the Fund(s) involved, the Adviser will have the right to vote such proxy, provided that it discloses the existence of the material conflict to the Chairperson of the Board as soon as practicable and to the Board at its next meeting. Any determination regarding the voting of proxies of the Fund that is made by the Board Members shall be deemed to be a good faith determination regarding the voting of proxies by the full Board.

V. Reports and Review

The Administrator shall make copies of each Form N-PX filed on behalf of the Fund available for the Boards’ review upon the Boards’ request. The Administrator (with input from the Adviser for the Fund) shall also provide any reports reasonably requested by the Board regarding the proxy voting records of the Fund.

The Adviser shall report any material changes to the Adviser Procedures to the Board as soon as practicable and the Boards will review the Adviser Procedures annually.

The Adviser also shall report any changes to the Adviser Procedures to the Fund Chief Legal Officer prior to implementing such changes in order to enable the Administrator to effectively coordinate the Fund’s disclosure relating to the Adviser Procedures.

To the extent requested by the Commission, the Policy and the Adviser Procedures shall be appended to the Fund’s statement of additional information included in its registration statement.

_____________________

The Eaton Vance Funds may be organized as trusts or corporations. For ease of reference, the Funds may be referred to herein as Trusts and the Funds’ Board of Trustees or Board of Directors may be referred to collectively herein as the Board.

An Adviser is expected to maintain a process for identifying a potential material conflict of interest. As an example only, such potential conflicts may arise when the issuer is a client of the Adviser and generates a significant amount of fees to the Adviser or the issuer is a distributor of the Adviser’s products.

If a material conflict of interest exists with respect to a particular proxy and the proxy voting procedures of the relevant Adviser require that proxies are to be voted in accordance with the recommendation of a third party proxy voting vendor, the requirements of this Section IV shall only apply if the Adviser intends to vote such proxy in a manner inconsistent with such third party recommendation.

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APPENDIX B

EATON VANCE MANAGEMENT

BOSTON MANAGEMENT AND RESEARCH

EATON VANCE INVESTMENT COUNSEL

EATON VANCE TRUST COMPANY

EATON VANCE MANAGEMENT (INTERNATIONAL) LIMITED

PROXY VOTING POLICIES AND PROCEDURES

I. Introduction

Eaton Vance Management, Boston Management and Research, Eaton Vance Investment Counsel, Eaton Vance Management (International) Limited and Eaton Vance Trust Company (each an “Adviser” and collectively the “Advisers”) have each adopted and implemented policies and procedures that each Adviser believes are reasonably designed to ensure that proxies are voted in the best interest of clients, in accordance with its fiduciary duties and, to the extent applicable, Rule 206(4)-6 under the Investment Advisers Act of 1940, as amended. The Advisers’ authority to vote the proxies of their clients is established by their advisory contracts or similar documentation, such as the Eaton Vance Funds Proxy Voting Policy and Procedures. These proxy policies and procedures reflect the U.S. Securities and Exchange Commission (“SEC”) requirements governing advisers and the long-standing fiduciary standards and responsibilities for ERISA accounts set out in the Department of Labor Bulletin 94-2 C.F.R. 2509.94-2 (July 29, 1994).

II. Overview

Each Adviser manages its clients’ assets with the overriding goal of seeking to provide the greatest possible return to such clients consistent with governing laws and the investment policies of each client. In pursuing that goal, each Adviser seeks to exercise its clients’ rights as shareholders of voting securities to support sound corporate governance of the companies issuing those securities with the principle aim of maintaining or enhancing the companies’ economic value.

The exercise of shareholder rights is generally done by casting votes by proxy at shareholder meetings on matters submitted to shareholders for approval (for example, the election of directors or the approval of a company’s stock option plans for directors, officers or employees). Each Adviser has established guidelines (“Guidelines”) as described below and generally will utilize such Guidelines in voting proxies on behalf of its clients. The Guidelines are largely based on those developed by the Agent (defined below) but also reflect input from the Global Proxy Group (defined below) and other Adviser investment professionals and are believed to be consistent with the views of the Adviser on the various types of proxy proposals. These Guidelines are designed to promote accountability of a company’s management and board of directors to its shareholders and to align the interests of management with those of shareholders. The Guidelines provide a framework for analysis and decision making but do not address all potential issues.

Except as noted below, each Adviser will vote any proxies received by a client for which it has sole investment discretion through a third-party proxy voting service (“Agent”) in accordance with the Guidelines in a manner that is reasonably designed to eliminate any potential conflicts of interest, as described more fully below. The Agent is currently Institutional Shareholder Services Inc. Where applicable, proxies will be voted in accordance with client-specific guidelines or, in the case of an Eaton Vance Fund that is sub-advised, pursuant to the sub-adviser’s proxy voting policies and procedures. Although an Adviser retains the services of the Agent for research and voting recommendations, the Adviser remains responsible for proxy voting decisions.

III. Roles and Responsibilities

A. Proxy Administrator

The Proxy Administrator and/or her designee coordinate the consideration of proxies referred back to the Adviser by the Agent, and otherwise administers these Procedures. In the Proxy Administrator’s absence, another employee of the Adviser may perform the Proxy Administrator’s responsibilities as deemed appropriate by the Global Proxy Group. The Proxy Administrator also may designate another employee to perform certain of the Proxy Administrator’s duties hereunder, subject to the oversight of the Proxy Administrator.

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B. Agent

The Agent is responsible for coordinating with the clients’ custodians and the Advisers to ensure that all proxy materials received by the custodians relating to the portfolio securities are processed in a timely fashion. Each Adviser shall instruct the custodian for its clients to deliver proxy ballots and related materials to the Agent. The Agent shall vote and/or refer all proxies in accordance with the Guidelines. The Agent shall retain a record of all proxy votes handled by the Agent. With respect to each Eaton Vance Fund memorialized therein, such record must reflect all of the information required to be disclosed in the Fund’s Form N-PX pursuant to Rule 30b1-4 under the Investment Company Act of 1940, to the extent applicable. In addition, the Agent is responsible for maintaining copies of all proxy statements received by issuers and to promptly provide such materials to an Adviser upon request.

Subject to the oversight of the Advisers, the Agent shall establish and maintain adequate internal controls and policies in connection with the provision of proxy voting services to the Advisers, including methods to reasonably ensure that its analysis and recommendations are not influenced by a conflict of interest, and shall disclose such controls and policies to the Advisers when and as provided for herein. Unless otherwise specified, references herein to recommendations of the Agent shall refer to those in which no conflict of interest has been identified. The Advisers are responsible for the ongoing oversight of the Agent as contemplated by SEC Staff Legal Bulletin No. 20 (June 30, 2014). Such oversight currently may include one or more of the following:

•

periodic review of Agent’s proxy voting platform and reporting capabilities (including recordkeeping);

•

periodic review of a sample of ballots for accuracy and correct application of the Guidelines;

•

periodic meetings with Agent’s client services team;

•

periodic in-person and/or web-based due diligence meetings;

•

receipt and review of annual certifications received from the Agent; and/or

•

annual review of due diligence materials provided by the Agent, including review of procedures and practices regarding potential conflicts of interests.

C. Global Proxy Group

The Adviser shall establish a Global Proxy Group which is responsible for establishing the Guidelines (described below) and reviewing such Guidelines at least annually. The Global Proxy Group shall also review recommendations to vote proxies in a manner that is contrary to the Guidelines and when the proxy relates to a conflicted company of the Adviser or the Agent as described below.

The members of the Global Proxy Group shall include the Chief Equity Investment Officer of Eaton Vance Management (“EVM”) and selected members of the Equity Departments of EVM and Eaton Vance Management (International) Limited (“EVMI”) and EVM’s Global Income Department. The Proxy Administrator is not a voting member of the Global Proxy Group. Members of the Global Proxy Group may be changed from time to time at the Advisers’ discretion. Matters that require the approval of the Global Proxy Group may be acted upon by its member(s) available to consider the matter.

IV. Proxy Voting

A. The Guidelines

The Global Proxy Group shall establish recommendations for the manner in which proxy proposals shall be voted (the “Guidelines”). The Guidelines shall identify when ballots for specific types of proxy proposals shall be voted¹or referred to the Adviser. The Guidelines shall address a wide variety of individual topics, including, among other matters, shareholder voting rights, anti-takeover defenses, board structures, the election of directors, executive and director compensation, reorganizations, mergers, issues of corporate social responsibility and other proposals affecting shareholder rights. In determining the Guidelines, the Global Proxy Group considers the recommendations of the Agent as well as input from the Advisers’ portfolio managers and analysts and/or other internally developed or third party research.

The Global Proxy Group shall review the Guidelines at least annually and, in connection with proxies to be voted on behalf of the Eaton Vance Funds, the Adviser will submit amendments to the Guidelines to the Fund Boards each year for approval.

With respect to the types of proxy proposals listed below, the Guidelines will generally provide as follows:

1. Proposals Regarding Mergers and Corporate Restructurings/Disposition of Assets/Termination/Liquidation and Mergers

The Agent shall be directed to refer proxy proposals accompanied by its written analysis and voting recommendation to the Proxy Administrator and/or her designee for all proposals relating to Mergers and Corporate Restructurings.

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2. Corporate Structure Matters/Anti-Takeover Defenses

As a general matter, the Advisers will normally vote against anti-takeover measures and other proposals designed to limit the ability of shareholders to act on possible transactions (except in the case of closed-end management investment companies).

3. Proposals Regarding Proxy Contests

The Agent shall be directed to refer contested proxy proposals accompanied by its written analysis and voting recommendation to the Proxy Administrator and/or her designee.

4. Social and Environmental Issues

The Advisers generally support management on social and environmental proposals.

Interpretation and application of the Guidelines is not intended to supersede any law, regulation, binding agreement or other legal requirement to which an issuer or the Adviser may be or become subject. The Guidelines generally relate to the types of proposals that are most frequently presented in proxy statements to shareholders. In certain circumstances, an Adviser may determine to vote contrary to the Guidelines subject to the voting procedures set forth below.

B. Voting Procedures

Except as noted in Section V below, the Proxy Administrator and/or her designee shall instruct the Agent to vote proxies as follows:

1. Vote in Accordance with Guidelines

If the Guidelines prescribe the manner in which the proxy is to be voted, the Agent shall vote in accordance with the Guidelines, which for certain types of proposals, are recommendations of the Agent made on a case-by-case basis.

2. Seek Guidance for a Referred Item or a Proposal for which there is No Guideline

If (i) the Guidelines state that the proxy shall be referred to the Adviser to determine the manner in which it should be voted or (ii) a proxy is received for a proposal for which there is no Guideline, the Proxy Administrator and/or her designee shall consult with the analyst(s) covering the company subject to the proxy proposal and shall instruct the Agent to vote in accordance with the determination of the analyst. The Proxy Administrator and/or her designee will maintain a record of all proxy proposals that are referred by the Agent, as well as all applicable recommendations, analysis and research received and the resolution of the matter. Where more than one analyst covers a particular company and the recommendations of such analysts for voting a proposal subject to this Section IV.B.2 conflict, the Global Proxy Group shall review such recommendations and any other available information related to the proposal and determine the manner in which it should be voted, which may result in different recommendations for clients (including Funds).

3. Votes Contrary to the Guidelines or Where Agent is Conflicted

In the event an analyst with respect to companies within his or her coverage area may recommend a vote contrary to the Guidelines, the Proxy Administrator and/or her designee will provide the Global Proxy Group with the Agent’s recommendation for the Proposal along with any other relevant materials, including a description of the basis for the analyst’s recommendation via email and the Proxy Administrator and/or her designee will then instruct the Agent to vote the proxy in the manner determined by the Global Proxy Group. The Adviser will provide a report to the Boards of Trustees of the Eaton Vance Funds reflecting any votes cast on behalf of the Eaton Vance Funds contrary to the Guidelines, and shall do so quarterly. A similar process will be followed if the Agent has a conflict of interest with respect to a proxy as described in Section VI.B.

4. Do Not Cast a Vote

It shall generally be the policy of the Advisers to take no action on a proxy for which no client holds a position or otherwise maintains an economic interest in the relevant security at the time the vote is to be cast. In addition, the Advisers may determine not to vote (i) if the economic effect on shareholders’ interests or the value of the portfolio holding is indeterminable or insignificant (e.g., proxies in connection with securities no longer held in the portfolio of a client or proxies being considered on behalf of a client that is no longer in existence); (ii) if the cost of voting a proxy outweighs the benefits (e.g., certain international proxies, particularly in cases in which share blocking practices may impose trading restrictions on the relevant portfolio security); or (iii) in markets in which shareholders’ rights are limited, and the Adviser is unable to timely access ballots or other proxy information. Non-Votes may also result in certain cases in which the Agent’s recommendation has been deemed to be conflicted, as provided for herein.

Eaton Vance Tax-Managed Buy-Write Income Fund

SAI dated April ___, 2017

C. Securities on Loan

When a fund client participates in the lending of its securities and the securities are on loan at the record date for a shareholder meeting, proxies related to such securities generally will not be forwarded to the relevant Adviser by the fund’s custodian and therefore will not be voted. In the event that the Adviser determines that the matters involved would have a material effect on the applicable fund’s investment in the loaned securities, the Adviser will make reasonable efforts to terminate the loan in time to be able to cast such vote or exercise such consent. The Adviser shall instruct the fund’s security lending agent to refrain from lending the full position of any security held by a fund to ensure that the Adviser receives notice of proxy proposals impacting the loaned security.

V. Recordkeeping

The Advisers will maintain records relating to the proxies they vote on behalf of their clients in accordance with Section 204-2 of the Investment Advisers Act of 1940, as amended. Those records will include:

•

A copy of the Advisers’ proxy voting policies and procedures;

•

Proxy statements received regarding client securities. Such proxy statements received from issuers are either in the SEC’s EDGAR database or are kept by the Agent and are available upon request;

•

A record of each vote cast;

•

A copy of any document created by the Advisers that was material to making a decision on how to vote a proxy for a client or that memorializes the basis for such a decision; and

•

Each written client request for proxy voting records and the Advisers’ written response to any client request (whether written or oral) for such records.

All records described above will be maintained in an easily accessible place for five years and will be maintained in the offices of the Advisers or their Agent for two years after they are created.

Notwithstanding anything contained in this Section V, Eaton Vance Trust Company shall maintain records relating to the proxies it votes on behalf of its clients in accordance with laws and regulations applicable to it and its activities. In addition, EVMI shall maintain records relating to the proxies it votes on behalf of its clients in accordance with UK law.

VI. Assessment of Agent and Identification and Resolution of Conflicts with Clients

A. Assessment of Agent

The Advisers shall establish that the Agent (i) is independent from the Advisers, (ii) has resources that indicate it can competently provide analysis of proxy issues, and (iii) can make recommendations in an impartial manner and in the best interests of the clients and, where applicable, their beneficial owners. The Advisers shall utilize, and the Agent shall comply with, such methods for establishing the foregoing as the Advisers may deem reasonably appropriate and shall do so not less than annually as well as prior to engaging the services of any new proxy voting service. The Agent shall also notify the Advisers in writing within fifteen (15) calendar days of any material change to information previously provided to an Adviser in connection with establishing the Agent’s independence, competence or impartiality.

B. Conflicts of Interest

As fiduciaries to their clients, each Adviser puts the interests of its clients ahead of its own. In order to ensure that relevant personnel of the Advisers are able to identify potential material conflicts of interest, each Adviser will take the following steps:

•

Quarterly, the Eaton Vance Legal and Compliance Department will seek information from the department heads of each department of the Advisers and of Eaton Vance Distributors, Inc. (“EVD”) (an affiliate of the Advisers and principal underwriter of certain Eaton Vance Funds). Each department head will be asked to provide a list of significant clients or prospective clients of the Advisers or EVD.

•

A representative of the Legal and Compliance Department will compile a list of the companies identified (the “Conflicted Companies”) and provide that list to the Proxy Administrator.

•

The Proxy Administrator will compare the list of Conflicted Companies with the names of companies for which he or she has been referred a proxy statement (the “Proxy Companies”). If a Conflicted Company is also a Proxy Company, the Proxy Administrator will report that fact to the Global Proxy Group.

Eaton Vance Tax-Managed Buy-Write Income Fund

SAI dated April ___, 2017

•

If the Proxy Administrator expects to instruct the Agent to vote the proxy of the Conflicted Company strictly according to the Guidelines contained in these Proxy Voting Policies and Procedures (the “Policies”) or the recommendation of the Agent, as applicable, he or she will (i) inform the Global Proxy Group of that fact, (ii) instruct the Agent to vote the proxies and (iii) record the existence of the material conflict and the resolution of the matter.

•

If the Proxy Administrator intends to instruct the Agent to vote in a manner inconsistent with the Guidelines, the Global Proxy Group will then determine if a material conflict of interest exists between the relevant Adviser and its clients (in consultation with the Legal and Compliance Department if needed). If the Global Proxy Group determines that a material conflict exists, prior to instructing the Agent to vote any proxies relating to these Conflicted Companies the Adviser will seek instruction on how the proxy should be voted from:

•

The client, in the case of an individual, corporate, institutional or benefit plan client;

•

In the case of a Fund, its board of directors, any committee, sub-committee or group of Independent Trustees (as long as such committee, sub-committee or group contains at least two or more Independent Trustees); or

•

The adviser, in situations where the Adviser acts as a sub-adviser to such adviser.

The Adviser will provide all reasonable assistance to each party to enable such party to make an informed decision.

If the client, Fund board or adviser, as the case may be, fails to instruct the Adviser on how to vote the proxy, the Adviser will generally instruct the Agent, through the Proxy Administrator, to abstain from voting in order to avoid the appearance of impropriety. If however, the failure of the Adviser to vote its clients’ proxies would have a material adverse economic impact on the Advisers’ clients’ securities holdings in the Conflicted Company, the Adviser may instruct the Agent, through the Proxy Administrator, to vote such proxies in order to protect its clients’ interests. In either case, the Proxy Administrator will record the existence of the material conflict and the resolution of the matter.

The Advisers shall also identify and address conflicts that may arise from time to time concerning the Agent. Upon the Advisers’ request, which shall be not less than annually, and within fifteen (15) calendar days of any material change to such information previously provided to an Adviser, the Agent shall provide the Advisers with such information as the Advisers deem reasonable and appropriate for use in determining material relationships of the Agent that may pose a conflict of interest with respect to the Agent’s proxy analysis or recommendations. Such information shall include, but is not limited to, a monthly report from the Agent detailing the Agent’s Corporate Securities Division clients and related revenue data. The Advisers shall review such information on a monthly basis. The Proxy Administrator shall instruct the Agent to refer any proxies for which a material conflict of the Agent is deemed to be present to the Proxy Administrator. Any such proxy referred by the Agent shall be referred to the Global Proxy Group for consideration accompanied by the Agent’s written analysis and voting recommendation. The Proxy Administrator will instruct the Agent to vote the proxy as recommended by the Global Proxy Group.

____________________

The Guidelines will prescribe how a proposal shall be voted or provide factors to be considered on a case-by-case basis by the Agent in recommending a vote pursuant to the Guidelines.

Eaton Vance Tax-Managed Buy-Write Income Fund

SAI dated April ___, 2017

APPENDIX C

PARAMETRIC PORTFOLIO ASSOCIATES LLC

PROXY VOTING POLICIES AND PROCEDURES

Policy

Parametric Portfolio Associates LLC (“Parametric”) has adopted and implemented these policies and procedures which it believes are reasonably designed to ensure that proxies are voted in the best interests of clients, in accordance with its fiduciary obligations and applicable regulatory requirements. When it has been delegated the responsibility to vote proxies on behalf of a client, Parametric will generally vote them in accordance with its Proxy Voting Guidelines, attached hereto as Exhibit A. The Proxy Voting Guidelines are set and annually reviewed by the firm’s Proxy Voting Committee. Parametric will consider potential conflicts of interest when voting proxies and disclose material conflicts to clients. Parametric will promptly provide these policies and procedures, as well as proxy voting records, to its clients upon request. As required, Parametric will retain appropriate proxy voting books and records. In the event that Parametric engages a third party to administer and vote proxies on behalf a client, it will evaluate the service provider’s conflicts of interest procedures and confirm its abilities to vote proxies in the client’s best interest.

Regulatory Requirements

Rule 206(4)-6 under the Investment Advisers Act requires that an investment adviser that exercises voting authority over client proxies to adopt and implement policies and procedures that are reasonably designed to ensure that the adviser votes proxies in the best interest of the client. The rule specifically requires that the policies and procedures describe how the adviser addresses material conflicts of interest with respect to proxy voting. The rule also requires an adviser to disclose to its clients information about those policies and procedures, and how the client may obtain information on how the adviser has voted the client’s proxies. In addition, Rule 204-2 under the Act requires an adviser to retain certain records related to proxy voting.

Responsibility

The Proxy Voting Coordinator is responsible for the day-to-day administration of the firm’s proxy voting practices, including voting proxies on behalf of clients. The Proxy Voting Committee is responsible for monitoring Parametric’s proxy voting practices, reviewing Parametric’s proxy voting guidelines on an annual basis, and evaluating any service providers engaged to vote proxies on behalf of clients. The Compliance Department is responsible for annually reviewing these policies and procedures to verify that they are adequate, appropriate and effective.

Procedures

Parametric has adopted and implemented procedures to ensure the firm’s proxy voting policies are observed, executed properly and amended or updated, as appropriate. The procedures are summarized as follows:

New Accounts

Parametric is generally delegated the responsibility to vote proxies on behalf of clients. This responsibility is typically established in the investment advisory agreement between the client and Parametric. If not set forth in the advisory agreement, Parametric will assume the responsibility to vote proxies on the client’s behalf unless it has received written instruction from the client not to.

Clients who seek to invest in a socially responsible manner can direct Parametric to vote certain resolutions in a manner that encourages high environmental, social and governance standards. Parametric has modified its proxy voting guidelines for clients that have provided written instruction to Parametric to vote in this manner. These Responsible Investing Proxy Voting Guidelines are attached hereto as Exhibit B (the “RI Proxy Voting Guidelines”).

On a monthly basis, Operations performs a reconciliation to ensure that Parametric is receiving and voting proxies for all client accounts, including new client accounts, for which it is responsible for voting client proxies.

Proxy Voting Administration

Parametric’s proxy voting is administered on a daily basis by a Proxy Voting Coordinator, who is a member of Parametric’s Operations Department. The Coordinator is responsible for ensuring proxies are received and voted in accordance with Parametric’s Proxy Voting Guidelines, RI Proxy Voting Guidelines or other specified guidelines set and provided by a client.

Eaton Vance Tax-Managed Buy-Write Income Fund

SAI dated April ___, 2017

Parametric utilizes Broadridge’s ProxyEdge, an automated tool which enables the firm to manage, track, reconcile and report proxy voting. Parametric utilizes ProxyEdge to ensure that all proxies are received and voted in timely manner. ProxyEdge receives a daily, automated feed from Parametric’s internal accounting system which contains real-time client accounts and holdings data.

In the event that Parametric receives a proxy issue that is not addressed in its Proxy Voting Guidelines, the Proxy Voting Coordinator will consult with an Operations Supervisor to confirm that the firm’s guidelines do not apply to the proxy issue. If confirmed, the Coordinator will forward the proxy to an appropriate Portfolio Manager for a decision how to vote the proxy in the client’s best interest. The Portfolio Manager’s decision will be documented by the Coordinator and reported to the Proxy Voting Committee for review at their next meeting.

The Coordinator may abstain from voting a proxy on behalf of a client account if the economic effect on shareholders’ interests or the value of the holding is indeterminable or insignificant (e.g., the security is no longer held in the client portfolio) or if the cost of voting the proxy outweighs the potential benefit (e.g., international proxies which share blocking practices may impose trading restrictions). The Proxy Voting Committee will review all abstentions to confirm they were in the client’s best interest.

A secondary review of proxy votes submitted by the Proxy Voting Coordinator is performed by an Operations Supervisor on a regular basis, to verify that the Coordinator has voted all proxies and voted them consistent with the appropriate proxy voting guidelines.

Proxy Voting Committee

Parametric has established a Proxy Voting Committee (the “Committee”), which shall meet on a quarterly basis to oversee and monitor the firm’s proxy voting practices. The Committee’s charter is attached hereto as Exhibit B.

The Committee will consider requests (from clients or Portfolio Managers) to vote a proxy contrary to the firm’s Proxy Voting Guidelines. The Committee will document its rationale for approving or denying the request.

On an annual basis, the Committee will review and, if necessary, revise the firm’s Proxy Voting Guidelines to ensure they are current, appropriate and designed to serve the best interests of clients and fund shareholders.

In the event that Parametric deems it to be in a client’s best interest to engage a third party to vote client proxies, the Committee will exercise due diligence to ensure that the third party firm can make recommendations and or vote proxies in an impartial manner and in the best interest of the client. This evaluation will consider the proxy voting firm’s business and conflict of interest procedures, and confirm that the procedures address the firm’s conflicts. On an annual basis, the Committee will evaluate the performance any third-party proxy voting firms and reconsider if changes have impacted their conflict of interest procedures. Initial and ongoing due diligence evaluations shall be documented in writing.

Conflicts of interest

The Proxy Voting Committee will identify and actively monitor potential material conflicts of interest which may compromise Parametric’s ability to vote a proxy issue in the best interest of clients. The Committee will maintain a list of Potential Material Conflicts related to proxy voting and provide it to the Proxy Voting Coordinator whenever it is updated. The list shall identify potential conflicts resulting from business relationships with clients, potential clients, service providers, and the firm’s affiliates.

Each proxy is reviewed by the Proxy Voting Coordinator to assess the extent to which there may be a material conflict between Parametric’s interests and those of the client. The Coordinator may consult with the Operations Supervisor to determine if a potential conflict exists. If so determined, the Coordinator will report the potential conflict to the Proxy Voting Committee, which will consider the relevant facts and determine if the conflict is material. If not, the proxy will be voted in accordance with Parametric’s Proxy Voting Guidelines.

If the Proxy Voting Committee determines a material conflict exists, Parametric will refrain from voting the proxy until it has disclosed the conflict to clients and obtain their consent or instruction as how to vote the proxy. Parametric shall provide all necessary information to clients when seeking their instruction and/or consent in voting the proxy.

If a client is unresponsive and fails to provide Parametric with instruction or consent to vote the proxy, the Proxy Voting Committee shall make a good faith determination as how to vote the proxy (which may include abstaining from voting the proxy) and provide appropriate instruction to the Proxy Voting Coordinator. The Committee shall document the rationale for making its final determination.

Eaton Vance Tax-Managed Buy-Write Income Fund

SAI dated April ___, 2017

Proxy Voting Disclosure Responsibilities

As a sub-adviser to various mutual funds registered under the Investment Company Act of 1940, Parametric will, upon each fund’s request, compile and transmit in a timely manner all data required to be filed on Form N-PX to the appropriate fund’s administrator or third party service provider designated by the fund’s administrator.

Parametric will promptly report any material changes to these policies and procedures to its mutual fund clients in accordance with their respective policies and procedures, to ensure that the revised policies and procedures may be properly reviewed by the funds’ Boards of Trustees/Directors and included in the funds’ annual registration statements.

Solicitations and Information Requests

Parametric’s proxy voting policies and procedures are summarized and described to clients in Item 17 of the firm’s Form ADV Brochure (Form ADV Part 2A). Parametric will promptly provide a copy of these proxy voting policies and procedures, which may be updated from time to time, to a client upon their request.

Parametric’s Form ADV Brochure discloses to clients how they may obtain information from Parametric about how it voted proxies on their behalf. Parametric will provide proxy voting information free of charge upon written request.

Parametric will not reveal or disclose to any third-party how it may have voted or intends to vote a proxy until its vote has been counted at the respective shareholder’s meeting. Parametric may in any event disclose its general voting guidelines. No employee of Parametric may accept any benefit in the solicitation of proxies.

Compliance Review

On a regular basis, but not less than annually, the Compliance Department will review proxy voting to verify that Parametric has voted proxies in accordance with the firm’s proxy voting guidelines and in clients’ best interests.

On an annual basis, the Compliance Department will review the firm’s proxy voting policies and procedures to confirm that they are adequate, effective, and designed to ensure that proxies are voted in clients’ best interests.

Class Actions

Parametric generally does not file or respond to class action claims on behalf of clients unless specifically obligated to do so under the terms of the client’s investment advisory agreement. Parametric will retain appropriate documentation regarding any determinations made on behalf of a client with regard to a class action claim or settlement.

Recordkeeping

Parametric will maintain proxy voting books and records in an easily accessible place for a period of six years, the first two years in the Seattle Investment Center.

Parametric will maintain all requisite proxy voting books and records, including but not limited to: (1) proxy voting policies and procedures, (2) proxy statements received on behalf of client accounts, (3) proxies voted, (4) copies of any documents that were material to making a decision how to vote proxies, and (5) client requests for proxy voting records and Parametric’s written response to any client request.

Eaton Vance Tax-Managed Buy-Write Income Fund

SAI dated April ___, 2017

Eaton Vance Tax-Managed Buy-Write Income Fund

Statement of Additional Information

April ___, 2017

________________

Investment Adviser and Administrator of

Eaton Vance Tax-Managed Buy-Write Income Fund

Eaton Vance Management

Two International Place

Boston, MA 02110

Sub-Adviser of

Eaton Vance Tax-Managed Buy-Write Income Fund

Parametric Portfolio Associates LLC

1918 Eighth Avenue, Suite 3100

Seattle, WA 98101

Custodian

State Street Bank and Trust Company

State Street Financial Center, One Lincoln Street

Boston, MA 02111

Transfer Agent

American Stock Transfer & Trust Company, LLC

6201 15^th Avenue

Brooklyn, NY 11219

Independent Registered Public Accounting Firm

Deloitte & Touche LLP

200 Berkeley Street

Boston, MA 02116

Eaton Vance Tax-Managed Buy-Write Income Fund

SAI dated [________], 2017

PARTC2

PART C

OTHER INFORMATION

ITEM 25.

FINANCIAL STATEMENTS AND EXHIBITS

(1)

FINANCIAL STATEMENTS:

Included in Part A:

Financial Highlights.

Included in Part B:

Registrant’s Certified Shareholder Report on Form N-CSR filed February 27, 2017 (Accession No. 0001193125-17-059204) and incorporated herein by reference.

_______________________________

(2)

EXHIBITS:


(a)	(1)	Agreement and Declaration of Trust dated November 17, 2004 filed as Exhibit (a) is incorporated herein by reference to the Registrant’s initial Registration Statement on Form N-2 (File Nos. 333-120666, 811-21676) as to the Registrant’s common shares of beneficial interest (“Common Shares”) filed with the Securities and Exchange Commission on November 22, 2004 (Accession No. 0000898432-04-000976) (“Initial Common Shares Registration Statement”).
	(2)	Amendment to Agreement and Declaration of Trust dated February 7, 2005 filed as Exhibit (a)(2) is incorporated herein by reference to Pre-Effective Amendment No. 1 to the Registrant’s initial Common Shares Registration Statement as filed with the Commission on March 23, 2005 (Accession No. 0000950135-05-001628) (“Pre-Effective Amendment No. 1”).
	(3)	Amendment to Agreement and Declaration of Trust dated August 11, 2008 filed as Exhibit (a)(3) is incorporated herein by reference to the Registrant’s initial Shelf Registration Statement on Form N-2 (File Nos. 333-214544, 811-21676) as to the Registrant’s common shares of beneficial interest (“Common Shares”) filed with the Securities and Exchange Commission on November 10, 2016 (Accession No. 0000940394-16-003206) (“Initial Common Shares Registration Statement”).
(b)		Amended and Restated By-Laws dated April 23, 2012 filed as Exhibit (b) is incorporated herein by reference to the Registrant’s Initial Common Shares Registration Statement.
(c)		Not applicable.
(d)		Form of Specimen Certificate for Common Shares of Beneficial Interest filed as Exhibit (d) is incorporated herein by reference to Pre-Effective Amendment No. 1.
(e)		Dividend Reinvestment Plan filed as Exhibit (e) is incorporated herein by reference to Pre-Effective Amendment No. 1.
(f)		Not applicable.
(g)	(1)	Investment Advisory Agreement between the Registrant and Eaton Vance Management dated February 7, 2005 filed as Exhibit (g)(1) is incorporated herein by reference to Pre-Effective Amendment No. 1.
	(2)	Investment Sub-Advisory Agreement between Eaton Vance Management and Parametric Portfolio Associates LLC dated February 7, 2005 filed as Exhibit (g)(3) is incorporated herein by reference to Pre-Effective Amendment No. 1.
(h)	(1)	Form of Underwriting Agreement filed as Exhibit (h) is incorporated herein by reference to Pre-Effective Amendment No. 1.

C-1


	(2)	Form of Master Selected Dealer Agreement filed as Exhibit (h)(2) is incorporated herein by reference to Pre-Effective Amendment No. 2 to the Registrant’s initial Common Shares Registration Statement as filed with the Commission on May 17, 2005 (Accession No. 0000950135-05-002147) (“Pre-Effective Amendment No. 2”).
	(3)	Form of Master Agreement among Underwriters filed as Exhibit (h)(3) is incorporated herein by reference to Pre-Effective Amendment No. 2.
	(4)	Form of Distribution Agreement with respect to the Rule 415 shelf offering filed herewith.
	(5)	Form of Sub-Placement Agent Agreement between Eaton Vance Distributors, Inc. and UBS Securities LLC filed herewith.
(i)		The Securities and Exchange Commission has granted the Registrant an exemptive order that permits the Registrant to enter into deferred compensation arrangements with its independent Trustees. See in the matter of Capital Exchange Fund, Inc., Release No. IC- 20671 (November 1, 1994).
(j)	(1)	Amended and Restated Master Custodian Agreement between Eaton Vance Funds and State Street Bank & Trust Company dated September 1, 2013 filed as Exhibit (g)(1) is incorporated herein by reference to Post-Effective Amendment No. 211 of Eaton Vance Mutual Funds Trust (File Nos. 002-90946, 811-04015) filed September 24, 2013 (Accession No. 0000940394-13-001073).
	(2)	Amended and Restated Services Agreement with State Street Bank & Trust Company dated September 1, 2010 filed as exhibit (g)(2) is incorporated herein by reference to Post-Effective Amendment No. 108 of Eaton Vance Special Investment Trust (File Nos. 02-27962, 811-1545) filed September 27, 2010 (Accession No. 0000940394-10-001000).
	(3)	Amendment Number 1 dated May 16, 2012 to Amended and Restated Services Agreement with State Street Bank & Trust Company dated September 1, 2010 filed as Exhibit (g)(3) is incorporated herein by reference to Post-Effective Amendment No. 39 of Eaton Vance Municipals Trust II (File Nos. 033-71320, 811-08134) filed May 29, 2012 (Accession No. 0000940394-12-000641).
	(4)	Amendment dated September 1, 2013 to Amended and Restated Services Agreement with State Street Bank & Trust Company filed as Exhibit (g)(4) is incorporated herein by reference to Post-Effective Amendment No. 211 of Eaton Vance Mutual Funds Trust (File Nos. 002-90946, 811-04015) filed September 24, 2013 (Accession No. 0000940394-13-001073).
(k)	(1)	Transfer Agency and Services Agreement dated February 5, 2007 between American Stock Transfer & Trust Company and each Registered Investment Company listed on Exhibit 1 filed as Exhibit (k)(1) is incorporated herein by reference to Pre-Effective Amendment No. 3 to the initial Registration Statement on Form N-2 of Eaton Vance Tax-Managed Global Diversified Equity Income Fund (File Nos. 333-138318, 811-21973) filed February 21, 2007 (Accession No. 0000950135- 07- 000974).
	(2)	Amendment dated April 21, 2008 to Transfer Agency and Services Agreement dated February 5, 2007 between American Stock Transfer & Trust Company and each Registered Investment Company listed on Exhibit 1 filed as Exhibit (k)(1) is incorporated herein by reference to Pre-Effective Amendment No. 1 to the initial Registration Statement on Form N-2 of Eaton Vance National Municipal Opportunities Trust (File Nos. 333-156948, 811-22269) filed April 21, 2009 (Accession No. 0000950135- 09- 083055).
	(3)	Amendment dated June 13, 2012 to Transfer Agency and Services Agreement dated February 5, 2007 between American Stock Transfer & Trust Company and each Registered Investment Company listed on Exhibit 1 filed as Exhibit (k)(1) is incorporated herein by reference to Pre-Effective Amendment No. 2 to the initial Registration Statement on Form N-2 of Eaton Vance High Income 2021 Target Term Trust (File Nos. 333-209436, 811-23136) filed April 25, 2016 (Accession No. 0000950135- 16- 552383).

C-2


	(4)	Amended and Restated Administrative Services Agreement dated August 6, 2012 between the Registrant and Eaton Vance Management filed as Exhibit (k)(4) is incorporated herein by reference to the Registrant’s Initial Common Shares Registration Statement..
	(5)	Form of Structuring Fee Agreement filed as Exhibit (k)(4) is incorporated herein by reference to Pre-Effective Amendment No. 1.
	(6)	Form of Organizational and Expense Reimbursement Arrangement filed as Exhibit (k)(5) is incorporated herein by reference to Pre-Effective Amendment No. 2.
	(7)	Form of Additional Compensation Agreement filed as Exhibit (k)(6) is incorporated herein by reference to Pre-Effective Amendment No. 2.
(l)		Opinion of Internal Counsel filed herewith.
(m)		Not applicable.
(n)		Consent of Independent Registered Public Accounting Firm filed herewith.
(o)		Not applicable.
(p)		Letter Agreement with Eaton Vance Management dated April 14, 2005 filed as Exhibit (p) is incorporated herein by reference to Pre-Effective Amendment No. 2.
(q)		Not applicable.
(r)	(1)	Code of Ethics adopted by the Eaton Vance Entities and the Eaton Vance Funds effective September 1, 2000, as revised February 8, 2017 filed as Exhibit (r) to Post-Effective Amendment No. 1 on Form N-2 of Eaton Vance Senior Floating-Rate Trust (File Nos. 333-207589, 811-21411) filed February 23, 2017 (Accession No. 0000940394-17-000321) and incorporated herein by reference.
	(2)	Code of Ethics adopted by Parametric Portfolio Associates effective March 2006 as revised September 15, 2015 filed as Exhibit (p)(2) to Post-Effective Amendment No. 99 of Eaton Vance Series Trust II (File Nos. 002-42722, 811-02258) filed October 26, 2015 (Accession No. 0000940394-15-001269) and incorporated herein by reference.
(s)		Power of Attorney dated October 18, 2016 filed as Exhibit (s) is incorporated herein by reference to the Registrant’s Initial Common Shares Registration Statement.

ITEM 26.

MARKETING ARRANGEMENTS

See Form of Distribution Agreement with respect to the Rule 415 shelf offering filed herewith.

See Form of Sub-Placement Agent Agreement between Eaton Vance Distributors, Inc. and UBS Securities LLC filed herewith.


ITEM 27.	OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION

The approximate expenses in connection with the offering are as follows:


Registration and Filing Fees	$ 5,541
FINRA Fees	$ 7,169
New York Stock Exchange Fees	$ 21,948
Costs of Printing and Engraving	$ 0
Accounting Fees and Expenses	$ 2,050
Legal Fees and Expenses	$ 500
Total	$ 37,208

C-3


ITEM 28.	PERSONS CONTROLLED BY OR UNDER COMMON CONTROL

None.

ITEM 29.

NUMBER OF HOLDERS OF SECURITIES

Set forth below is the number of record holders as of February 28, 2017, of each class of securities of the Registrant:


Title of Class		Number of Record Holders
Common Shares of Beneficial interest, par value $0.01 per share		18,826

ITEM 30.

INDEMNIFICATION

The Registrant's By-Laws, filed in the Registrant’s Initial Common Shares Registration Statement contain and the form of Underwriting Agreement filed in Pre-Effective Amendment No. 1 contains provisions limiting the liability, and providing for indemnification, of the Trustees and officers under certain circumstances.

Registrant's Trustees and officers are insured under a standard investment company errors and omissions insurance policy covering loss incurred by reason of negligent errors and omissions committed in their official capacities as such. Insofar as indemnification for liabilities arising under the Securities Act of 1933, as amended (the “Securities Act”), may be permitted to directors, officers and controlling persons of the Registrant pursuant to the provisions described in this Item 30, or otherwise, the Registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

ITEM 31.

BUSINESS AND OTHER CONNECTIONS OF INVESTMENT ADVISER

Reference is made to: (i) the information set forth under the caption “Investment advisory and other services” in the Statement of Additional Information; (ii) the Eaton Vance Corp. 10-K filed under the Securities Exchange Act of 1934 (File No. 001-8100); and (iii) the Form ADV of Eaton Vance Management (File No. 801-15930) filed with the Commission, all of which are incorporated herein by reference.

ITEM 32.

LOCATION OF ACCOUNTS AND RECORDS

All applicable accounts, books and documents required to be maintained by the Registrant by Section 31(a) of the Investment Company Act of 1940 and the Rules promulgated thereunder are in the possession and custody of the Registrant's custodian, State Street Bank and Trust Company, State Street Financial Center, One Lincoln Street, Boston, MA 02111, and its transfer agent, American Stock Transfer & Trust Company, LLC, 6201 15^th Avenue, Brooklyn, NY 11219, with the exception of certain corporate documents and portfolio trading documents which are in the possession and custody of Eaton Vance Management, Two International Place, Boston, MA 02110. Registrant is informed that all applicable accounts, books and documents required to be maintained by registered investment advisers are in the custody and possession of Eaton Vance Management.

ITEM 33.

MANAGEMENT SERVICES

Not applicable.

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ITEM 34.

UNDERTAKINGS

The Registrant undertakes to suspend offering of Common Shares until the prospectus is amended if (1) subsequent to the effective date of this Registration Statement, the net asset value declines more than 10 percent from its net asset value as of the effective date of this Registration Statement or (2) the net asset value increases to an amount greater than its net proceeds as stated in the prospectus.

Not applicable.

The Registrant undertakes to

(a)

file, during any period in which offers or sales are being made, a post-effective amendment to the registration statement:

(1)

to include any prospectus required by Section 10(a)(3) of the Securities Act;

(2)

to reflect in the prospectus any facts or events after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement;

(3)

to include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement.

(b)

that, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of those securities at that time shall be deemed to be the initial bona fide offering thereof;

(c)

to remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering;

(d)

that, for the purpose of determining liability under the Securities Act to any purchaser, if the Registrant is subject to Rule 430C: Each prospectus filed pursuant to Rule 497(b), (c), (d) or (e) under the Securities Act as part of a registration statement relating to an offering, other than prospectus filed in reliance on Rule 430A under the Securities Act, shall be deemed to be part of and included in the registration statement as of the date it is first used after effectiveness. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such first use, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such date of first use;

(e)

that for the purpose of determining liability of the Registrant under the Securities Act to any purchaser in the initial distribution of securities: The undersigned Registrant undertakes that in a primary offering of securities of the undersigned Registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned Registrant will be a seller to the purchaser and will be considered to offer or sell such securities to the purchaser:

(1)

any preliminary prospectus or prospectus of the undersigned Registrant relating to the offering required to be filed pursuant to Rule 497 under the Securities Act;

(2)

the portion of any advertisement pursuant to Rule 482 under the Securities Act relating to the offering containing material information about the undersigned Registrant or its securities provided by or on behalf of the undersigned Registrant; and

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(3)

any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser.

The Registrant undertakes that:

(a)

for the purpose of determining any liability under the Securities Act, the information omitted from the form of prospectus filed as part of this Registration Statement in reliance upon Rule 430A and contained in the form of prospectus filed by the Registrant pursuant to 497(h) under the Securities Act shall be deemed to be part of the Registration Statement as of the time it was declared effective; and

(b)

for the purpose of determining any liability under the Securities Act, each post- effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

The Registrant undertakes to send by first class mail or other means designed to ensure equally prompt delivery, within two business days of receipt of an oral or written request, its Statement of Additional Information.

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NOTICE

A copy of the Agreement and Declaration of Trust of Eaton Vance Tax-Managed Buy-Write Income Fund is on file with the Secretary of State of The Commonwealth of Massachusetts and notice is hereby given that this instrument is executed on behalf of the Registrant by an officer of the Registrant as an officer and not individually and that the obligations of or arising out of this instrument are not binding upon any of the Trustees, officers or shareholders individually, but are binding only upon the assets and property of the Registrant.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended and the Investment Company Act of 1940, as amended the Registrant has duly caused this Amendment to the Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized in the City of Boston and the Commonwealth of Massachusetts, on the 29^th day of March, 2017.


	EATON VANCE TAX-MANAGED BUY-WRITE INCOME FUND

	By:	/s/ Edward J. Perkin
		Edward J. Perkin, President

Pursuant to the requirements of the Securities Act of 1933, as amended this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.


Signature		Title

/s/ Edward J. Perkin		President (Chief Executive Officer)
Edward J. Perkin

/s/ James F. Kirchner		Treasurer (Principal Financial and Accounting Officer)
James F. Kirchner

Signature		Title	Signature	Title

Scott E. Eston*		Trustee	William H. Park*	Trustee
Scott E. Eston			William H. Park

Thomas E. Faust Jr.*		Trustee	Helen Frame Peters*	Trustee
Thomas E. Faust Jr.			Helen Frame Peters

Mark R. Fetting*		Trustee	Susan J. Sutherland*	Trustee
Mark R. Fetting			Susan J. Sutherland

Cynthia E. Frost*		Trustee	Harriett Tee Taggart*	Trustee
Cynthia E. Frost			Harriett Tee Taggart

George J. Gorman*		Trustee	Ralph F. Verni*	Trustee
George J. Gorman			Ralph F. Verni

Valerie A. Mosley*		Trustee	Scott E. Wennerholm*	Trustee
Valerie A. Mosley			Scott E. Wennerholm


*By:	/s/ Maureen A. Gemma
	Maureen A. Gemma (As attorney-in-fact)

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INDEX TO EXHIBITS


Exhibit No.		Description
(h)	(2)	Form of Distribution Agreement with respect to the Rule 415 shelf offering
	(3)	Form of Sub-Placement Agent Agreement between Eaton Vance Distributors, Inc. and UBS Securities LLC
(l)		Opinion of Internal Counsel
(n)		Consent of Independent Registered Public Accounting Firm

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