<PAGE>
January 1, 2000
FUND PROFILE
T. ROWE PRICE
Equity Index 500 Fund
A fund that seeks to match the performance of the Standard & Poor's 500 Stock
Index/(R)/, an index of common stocks.
This profile summarizes key information about the fund that is included in the
fund's prospectus. The fund's prospectus includes additional information about
the fund, including a more detailed description of the risks associated with
investing in the fund that you may want to consider before you invest. You may
obtain the prospectus and other information about the fund at no cost by calling
1-800-638-5660, or by visiting our Web site at www.troweprice.com.
T ROWE PRICE LOGO
<PAGE>
<PAGE>
1
FUND PROFILE
- ---------------------------------------------------------
What is the fund's objective?
To match the performance of the Standard & Poor's 500 Stock Index/(R)/. The
S&P 500 is made up of primarily large-capitalization companies that represent
a broad spectrum of the U.S. economy and about 70% of the U.S. stock market's
total capitalization. (Market capitalization is the number of a company's
outstanding shares multiplied by the market price per share.)
"Standard & Poor's," "S&P," "S&P 500," Standard & Poor's 500," and "500" are
trademarks of The McGraw-Hill Companies, Inc. and have been licensed for use
by T. Rowe Price Index Trust, Inc. The fund is not sponsored, endorsed, sold,
or promoted by Standard & Poor's, and Standard & Poor's makes no
representation regarding the advisability of investing in the product.
What is the fund's principal investment strategy?
The fund invests substantially all of its assets in all of the stocks in the
S&P 500 Index. We attempt to maintain holdings of each stock in proportion to
its weight in the index. This is known as a full replication strategy.
Standard & Poor's constructs the index by first identifying major industry
categories and then allocating a representative sample of the larger and more
liquid stocks in those industries to the index. S&P weights each stock
according to its total market value. The 50 largest companies in the index
currently account for over 50% of its value.
T. Rowe Price continually compares the composition of the fund to that of the
index. If a misweighting develops, the portfolio is rebalanced in an effort
to bring it into line with the index. When investing cash flow, the fund may
purchase stocks, stock index futures, or stock options. This approach is
intended to minimize any deviations in performance between the fund and
index.
The fund intends to remain fully invested during all market conditions. The
fund may sell securities primarily to rebalance its portfolio or satisfy
redemption requests.
Further information about the fund's investments, including a review of
market conditions and fund strategies and their impact on performance, is
available in the annual and semiannual shareholder reports. To obtain free
copies of any of these documents, call 1-800-638-5660.
What are the main risks of investing in the fund?
The fund is designed to track broad segments of the stock market--whether
they are rising or falling. Markets as a whole can decline for many reasons,
including adverse political or economic developments here or abroad, changes
in investor psychology, or heavy institutional selling.
<PAGE>
2
2
FUND PROFILE
- ---------------------------------------------------------
Since the fund is passively managed and seeks to remain fully invested at all
times, assets cannot be shifted from one stock or group of stocks to another
based on their prospects, or from stocks into bonds or cash equivalents in an
attempt to cushion the impact of a market decline. Therefore, actively
managed funds may outperform this fund. In addition, fund returns are likely
to be slightly below those of the index because the fund has fees and
transaction expenses while indices have none. The timing of cash flows and a
fund's size can also influence returns. While there is no guarantee, the
investment manager expects the correlation between the fund and the index to
be at least .95. A correlation of 1.00 means the return of a fund can be
completely explained by the return of an index. Finally, large-cap stocks may
at times lag shares of smaller, faster-growing companies.
If the fund uses futures and options, it is exposed to additional volatility
and potential losses.
As with any mutual fund, there can be no guarantee the fund will achieve its
objective.
. The fund's share price may decline, so when you sell your shares, you may
lose money. An investment in the fund is not a deposit of a bank and is not
insured or guaranteed by the Federal Deposit Insurance Corporation or any
other government agency.
How can I tell if the fund is appropriate for me?
Consider your investment goals, your time horizon for achieving them, and
your tolerance for risk. The S&P 500 Index is one of the most widely tracked
stock indices in the world. If you seek a relatively low-cost way of
participating in the U.S. equity markets through a passively managed
portfolio and want to closely match the performance of the mostly large-cap
stocks in this index, with the same level of risk, the fund may be an
appropriate choice. The fund should not represent your complete investment
program or be used for short-term trading purposes.
The fund can be used in both regular and tax-deferred accounts, such as IRAs.
. Equity investors should have a long-term investment horizon and be willing
to wait out bear markets.
How has the fund performed in the past?
The bar chart and the average annual total return table indicate risk by
illustrating how much returns can differ from one year to the next. The
fund's past performance is no guarantee of its future returns.
The fund can also experience short-term performance swings, as shown by the
best and worst calendar quarter returns during the years depicted in the
chart.
<PAGE>
3
FUND PROFILE
- ---------------------------------------------------------
LOGO
<TABLE>
<CAPTION>
Calendar Year Total Returns*
"90" "91" "92" "93" "94" "95" "96" "97" "98" "99"
----------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C>
0.31 29.21 7.19 9.42 1.01 37.16 22.65 32.87 28.31 20.64
----------------------------------------------------------------------
</TABLE>
Quarter ended Total return
Best quarter 12/31/98 21.31%
Worst quarter 9/30/90 -13.25%
<TABLE>
Table 1 Average Annual Total Returns
<CAPTION>
Periods ended
December 31, 1999
Since inception
1 year 5 years (03/30/1990)
------------------------
<S> <C> <C> <C>
Equity Index 500 Fund 20.64% 28.18% 18.67%
S&P 500 Stock Index 21.04 28.56 19.08
------------------------------------------------------------
</TABLE>
These figures include changes in principal value, reinvested dividends, and
capital gain distributions, if any.
Does not include account maintenance fee which, if reflected, would reduce the
returns shown.
What fees or expenses will I pay?
The fund is 100% no load. However, the fund charges a redemption fee of
0.50%, payable to the fund, for shares held less than six months, and a
quarterly maintenance fee of $2.50 for accounts of less than $10,000. There
are no other fees or charges to buy or sell fund shares, reinvest dividends,
or exchange into other T. Rowe Price funds. There are no 12b-1 fees.
<PAGE>
4
4
FUND PROFILE
- ---------------------------------------------------------
<TABLE>
Table 2 Fees and Expenses of the Fund
<CAPTION> Shareholder fees (fees
paid directly from your Annual fund operating expenses
investment) (expenses that are deducted from fund assets)
Total
Account annual fund Fee waiver/
Redemption maintenance Management Other operating expense Net
fee fee/a/ fee expenses expenses reimbursement expenses
<S> <C> <C> <C> <C> <C> <C> <C> <S>
Equity Index 500 Fund 0.50% $10 0.15%/b/ 0.29% 0.44% 0.09% 0.35%/b/
-----------------------------------------------------------------------------------------------------------------
</TABLE>
/a/A $2.50 quarterly fee is charged for accounts with balances less than
$10,000.
/b/
To limit the fund's expenses, T. Rowe Price contractually obligated itself to
waive its fees and bear any expenses through December 31, 1999, which would
cause the fund's ratio of expenses to average net assets to exceed 0.40%.
Effective January 1, 2000, T. Rowe Price agreed to lower the expense
limitation to 0.35% and extend it for a period of one year through December
31, 2000. Fees waived or expenses paid or assumed under these agreements are
subject to reimbursement to T. Rowe Price by the fund whenever the fund's
expense ratio is below 0.35%; however, no reimbursement will be made after
December 31, 2001, or if it would result in the expense ratio exceeding
0.35%. Any amounts reimbursed will have the effect of increasing fees
otherwise paid by the fund.
Example. The following table gives you a rough idea of how expense ratios
may translate into dollars and helps you to compare the cost of investing in
this fund with that of other funds. Although your actual costs may be higher
or lower, the table shows how much you would pay if operating expenses remain
the same, the expense limitation currently in place is not renewed, you
invest $10,000, you earn a 5% annual return, and you hold the investment for
the following periods:
<TABLE>
<CAPTION>
1 year* 3 years* 5 years* 10 years*
----------------------------------------------------
<S> <C> <C> <C>
$41 $133 $238 $547
----------------------------------------------------
</TABLE>
* Does not include account maintenance fee for accounts of less than $10,000.
Who manages the fund?
The fund is managed by T. Rowe Price Associates, Inc. Founded in 1937, T.
Rowe Price and its affiliates manage investments for individual and
institutional accounts. The company offers a comprehensive array of stock,
bond, and money market funds directly to the investing public.
Richard T. Whitney manages the fund day-to-day and has been chairman of its
Investment Advisory Committee since 1990. He joined T. Rowe Price in 1985 and
has been managing investments since 1986.
<PAGE>
5
FUND PROFILE
- ---------------------------------------------------------
Note: The following questions and answers about buying and selling shares and
services do not apply to employer-sponsored retirement plans. If you are a
participant in one of these plans, please call your plan's toll-free number for
additional information.
How can I purchase shares?
Fill out the New Account Form and return it with your check in the postpaid
envelope. The minimum initial purchase is $2,500 ($1,000 for IRAs and gifts
or transfers to minors). The minimum subsequent investment is $100 ($50 for
IRAs, gifts or transfers to minors, or Automatic Asset Builder). You can also
open an account by bank wire, by exchanging from another T. Rowe Price fund,
or by transferring assets from another financial institution.
How can I sell shares?
You may redeem or sell any portion of your account on any business day.
Simply write to us or call. You can also access your account at any time via
Tele*Access /(R)/ or our Web site. We offer convenient exchange among our
entire family of domestic and international funds. Restrictions may apply in
special circumstances, and some redemption requests need a signature
guarantee. A $5 fee is charged for wire redemptions under $5,000.
When will I receive income and capital gain distributions?
The fund distributes income quarterly and net capital gains, if any, at
year-end. For regular accounts, income and short-term gains are taxable at
ordinary income rates, and long-term gains are taxable at the capital gains
rate. Distributions are reinvested automatically in additional shares unless
you choose another option, such as receiving a check. Distributions paid to
IRAs and employer-sponsored retirement plans are automatically reinvested.
What services are available?
A wide range, including but not limited to:
. retirement plans for individuals and large and small businesses;
. automated information and transaction services by telephone or computer;
. electronic transfers between fund and bank accounts;
. automatic investing and automatic exchange;
. brokerage services; and
. asset manager accounts.
<PAGE>
FUND PROFILE
- ---------------------------------------------------------
T. Rowe Price Associates, Inc.
100 East Pratt Street
Baltimore, MD 21202
www.troweprice.com
LOGO
RPS F50-035
T. Rowe Price Investment Services, Inc., Distributor
<PAGE>
