T. Rowe Price Equity Index 500 Fund

Price Equity Index 500 Fund

SUMMARY

Investment Objective

The fund seeks to match the performance of the Standard & Poor’s 500 Stock Index^®.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Fees and Expenses of the Fund

Shareholder fees (fees paid directly from your investment)

Shareholder Fees (USD $)		T. Rowe Price Equity Index 500 Fund
Maximum sales charge (load) imposed on purchases		none
Maximum deferred sales charge (load)		none
Redemption fee (as a percentage of amount redeemed on shares held for 90 days or less)		0.50%
Maximum account fee	[1]	20

Annual fund operating expenses

(expenses that you pay each year as a

percentage of the value of your investment)

Annual Fund Operating Expenses	T. Rowe Price Equity Index 500 Fund
Management fees	0.10%
Distribution and service (12b-1) fees	none
Other expenses	0.20%
Total annual fund operating expenses	0.30%

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 fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	1 year	3 years	5 years	10 years
T. Rowe Price Equity Index 500 Fund	31	97	169	381

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. During the most recent fiscal year, the fund’s portfolio turnover rate was 5.5% of the average value of its portfolio.

Investments, Risks, and Performance

Principal Investment Strategies

The fund seeks to match the performance of the S&P 500 Index by using a full replication strategy. This involves investing 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.

The S&P 500 is made up of primarily large-capitalization companies that represent a broad spectrum of the U.S. economy and a substantial part 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 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. For example, the 50 largest companies in the index may account for over 50% of its value.

Under normal conditions, the fund will invest at least 80% of its net assets (including any borrowings for investment purposes) in stocks that are held in its benchmark index. T. Rowe Price compares the composition of the fund to that of the index. If a material misweighting develops, the portfolio managers seek to rebalance the portfolio in an effort to realign it with its index.

While most assets will be invested in common stocks, the fund may also purchase stock index futures contracts. Futures would typically be used to reduce cash balances in the fund and increase the level of fund assets exposed to common stocks represented in the fund’s benchmark index.

While there is no guarantee, the correlation between the fund and its index is expected to be at least 0.95. A correlation of 1.00 indicates that the returns of the fund and the index will always move in the same direction (but not necessarily by the same amount). A correlation of 0.00 would mean movements in the fund are unrelated to movements in the index.

The fund may sell securities to better align its portfolio with the characteristics of its benchmark or to satisfy redemption requests. However, the fund is not required to sell specific securities that have been removed from its index.

Principal Risks

As with any mutual fund, there is no guarantee that the fund will achieve its objective. The fund’s share price fluctuates, which means you could lose money by investing in the fund. The principal risks of investing in this fund are summarized as follows:

Risks of stock investing Stocks generally fluctuate in value more than bonds and may decline significantly over short time periods. There is a chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The value of a stock in which the fund invests may decline due to general weakness in the stock market or because of factors that affect a company or a particular industry.

Market capitalization risk Investing primarily in issuers within the same market capitalization category carries the risk that the category may be out of favor due to current market conditions or investor sentiment. Securities issued by large-cap companies tend to be less volatile than securities issued by smaller companies. However, larger companies may not be able to attain the high growth rates of successful smaller companies, especially during strong economic periods, and may be unable to respond as quickly to competitive challenges.

Index investing risk Because the fund is passively managed and seeks to match the performance of its benchmark index, holdings are generally not reallocated based on changes in market conditions or outlook for a specific security, industry, or market sector. As a result, the fund’s performance may lag the performance of actively managed funds.

Tracking error The returns of the fund are expected to be slightly below the returns of its benchmark index (referred to as “tracking error”) because the fund incurs fees and transaction expenses while the index has no fees or expenses. The risk of tracking error is increased to the extent the fund is unable to fully replicate its index, which could result from changes in the composition of the index or the timing of purchases and redemptions of fund shares.

Futures risk To the extent the fund uses futures, it is exposed to potential volatility and losses greater than direct investments in the contract’s underlying assets.

Performance

The bar chart showing calendar year returns and the average annual total returns table indicate risk by illustrating how much returns can differ from one year to the next and how fund performance compares with that of a comparable market index. The fund’s past performance (before and after taxes) is not necessarily an indication of future performance.

The fund can also experience short-term performance swings, as shown by the best and worst calendar quarter returns during the years depicted.

Equity Index 500 Fund

Calendar Year Returns

	Quarter	Total
	Ended	Return
Best Quarter	6/30/09	15.99%
Worst Quarter	12/31/08	-21.94%

In addition, the average annual total returns table shows hypothetical after-tax returns to suggest how taxes paid by a shareholder may influence returns. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as a 401(k) account or individual retirement account.

Average Annual Total Returns

Periods ended

December 31, 2011

Average Annual Total Returns	1 Year	5 Years	10 Years
T. Rowe Price Equity Index 500 Fund	1.87%	(0.46%)	2.67%
T. Rowe Price Equity Index 500 Fund Returns after taxes on distributions	1.59%	(0.74%)	2.38%
T. Rowe Price Equity Index 500 Fund Returns after taxes on distributions and sale of fund shares	1.57%	(0.41%)	2.24%
T. Rowe Price Equity Index 500 Fund S&P 500 Index	2.11%	(0.25%)	2.92%

Updated performance information is available through troweprice.com or may be obtained by calling 1-800-225-5132.

[1] Subject to certain exceptions, accounts with a balance of less than $10,000 are charged an annual $20 fee.