<PAGE>
EATON VANCE BALANCED FUND
Supplement to Prospectus
Dated May 1, 1999
1. THE FOLLOWING REPLACES THE THIRD PARAGRAPH ON PAGE 2 OF THE PROSPECTUS:
The Fund currently seeks its objective by investing in Capital Growth
Portfolio and High Grade Income Portfolio, separate registered investment
companies. The investment objective of Capital Growth Portfolio is to seek
growth of capital and the investment objectives of High Grade Income
Portfolio are to provide current income and total return.
2. THE FOLLOWING REPLACES THE "ANNUAL FUND OPERATING EXPENSES" TABLE AND
"EXAMPLE" UNDER "FUND SUMMARY" ON PAGE 3 OF THE PROSPECTUS:
<TABLE>
<CAPTION>
Annual Fund Operating Expenses (expenses that are deducted from Fund assets) Class A Class B Class C
---------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C>
Management Fees 0.61% 0.61% 0.61%
Distribution and Service (12b-1) Fees* 0.00% 0.94% 1.00%
Other Expenses** 0.36% 0.23% 0.23%
---- ----- ----
Total Annual Fund Operating Expenses 0.97% 1.78% 1.84%
</TABLE>
* Long-term shareholders of Class B and Class C shares may pay more than the
economic equivalent of the front-end sales charge permitted by the National
Association of Securities Dealers, Inc.
** Other Expenses for Class A shares includes a service fee of 0.13%.
EXAMPLE. This Example is intended to help you compare the cost of investing in
the Fund with the cost of investing in other mutual funds. The Example assumes
that you invest $10,000 in the Fund for the time periods indicated and then
redeem all of your shares at the end of those periods. The Example also assumes
that your investment has a 5% return each year and that the operating expenses
remain the same. Although your actual costs may be higher or lower, based on
these assumptions your costs would be:
1 Year 3 Years 5 Years 10 Years
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Class A shares $668 $866 $1,080 $1,696
Class B shares $681 $960 $1,164 $2,095
Class C shares $287 $579 $ 995 $2,159
You would pay the following expenses if you did not redeem you shares:
1 Year 3 Years 5 Years 10 Years
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Class A shares $668 $866 $1,080 $1,696
Class B shares $181 $560 $ 964 $2,095
Class C shares $187 $579 $ 995 $2,159
3. THE FOLLOWING REPLACES THE FIRST AND SECOND PARAGRAPH UNDER "INVESTMENT
OBJECTIVES & PRINCIPAL POLICIES AND RISKS" ON PAGE 10 OF THE PROSPECTUS:
The investment objectives and principal policies and risks of the Funds are set
forth below. Each Fund's investment objective may not be changed without
shareholder approval. Certain of a Fund's investment policies may be changed by
the Trustees without shareholder approval. Each Fund currently seeks its
investment objective by investing in one or more separate open-end investment
companies that have the same objective and policies as the Fund.
BALANCED FUND. Balanced Fund's investment objective is to provide current income
and long-term capital growth. The Fund currently invests in Capital Growth
Portfolio and High Grade Income Portfolio. The investment objective of Capital
Growth Portfolio is to seek growth of capital and the investment objectives of
High Grade Income Portfolio are to seek current income and total return.
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The Balanced Fund's allocation of assets to equity securities in the Capital
Growth Portfolio will generally not exceed 75% nor be less than 25% of net
assets. The Capital Growth Portfolio invests in a broadly diversified list of
seasoned securities representing a number of different industries. The portfolio
manager places emphasis on equity securities considered to be of high or
improving quality. The foregoing policies cannot be changed without shareholder
approval. Balanced Fund also allocates at least 25% of its net assets in
fixed-income securities in the High Grade Income Portfolio, which may include
preferred stocks, corporate bonds, U.S. Government securities, money market
instruments and mortgage-backed obligations. The High Grade Income Portfolio may
invest in fixed-income securities of any credit quality but will limit
investment in fixed-income securities rated below investment grade to not more
than 5% of the Balanced Fund's total assets.
4. THE FOLLOWING REPLACES THE SECOND PARAGRAPH UNDER "MANAGEMENT AND
ORGANIZATION" ON PAGE 12 OF THE PROSPECTUS:
The investment adviser manages the investments of each Portfolio and provides
related office facilities and personnel. Under its investment advisory
agreements with Capital Growth Portfolio and High Grade Income Portfolio, BMR
receives a monthly advisory fee from each Portfolio of 5/96 of 1% (equivalent to
0.625% annually) of the average daily net assets up to and including $300
million, and 1/24 of 1% (equivalent to 0.50% annually) of the average daily net
assets over $300 million. If the net assets of the Fund, including its
investments in the Capital Growth and High Grade Income Portfolios, exceed $300
million, Eaton Vance will take actions to maintain the expenses of the Fund as
if an advisory fee breakpoint had been reached on the net assets of the Fund.
5. THE FOLLOWING REPLACES THE FIFTH PARAGRAPH UNDER "MANAGEMENT AND
ORGANIZATION" ON PAGE 12 OF THE PROSPECTUS:
Arieh Coll is the portfolio manager of the Capital Growth Portfolio (since it
commenced operations). He has been an Eaton Vance portfolio manager since
January 2000 and is Vice President of Eaton Vance and BMR. Prior to joining
Eaton Vance, Mr. Coll was employed by Fidelity Investments as a portfolio
manager. Michael B. Terry is the portfolio manager of High Grade Income
Portfolio (since it commenced operations). He also manages other Eaton Vance
portfolios, has been an Eaton Vance portfolio manager for more than 5 years, and
is a Vice President of Eaton Vance and BMR.
March 1, 2000 BALPS
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