SUMMARY PROSPECTUS May 1, 2021
		T. ROWE PRICE
PEXMX		Extended Equity Market Index Fund
	The Securities and Exchange Commission (SEC) has not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense. Before you invest, you may want to review the fund’s prospectus, which contains more information about the fund and its risks. You can find the fund’s prospectus, shareholder reports, and other information about the fund online at troweprice.com/prospectus. You can also get this information at no cost by calling 1-800-638-5660, by sending an e-mail request to info@troweprice.com, or by contacting your financial intermediary. This Summary Prospectus incorporates by reference the fund’s prospectus, dated May 1, 2021, as amended or supplemented, and Statement of Additional Information, dated May 1, 2021, as amended or supplemented.

SUMMARY 1

Investment Objective(s)

The fund seeks to track the performance of a benchmark index that measures the investment return of small- and mid-capitalization U.S. stocks.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the fund. You may also incur brokerage commissions and other charges when buying or selling shares of the fund, which are not reflected in the table.

Fees and Expenses of the Fund

Shareholder fees (fees paid directly from your investment)
Maximum account fee	$20	a
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)
Management fees	0.35	%
Distribution and service (12b-1) fees	—
Other expenses	—
Total annual fund operating expenses	0.35

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

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, 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:

1 year	3 years	5 years	10 years
$36	$113	$197	$443

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 the fund’s 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 35.9% of the average value of its portfolio.

Investments, Risks, and Performance

Principal Investment Strategies

Under normal conditions, the fund will invest at least 80% of its net assets (including any borrowings for investment purposes) in stocks that are included in its benchmark index. The

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fund does not attempt to fully replicate the index by owning each of the stocks in the index. The fund uses a sampling strategy, investing substantially all of its assets in a group of stocks representative of the sector allocations, financial characteristics, and other attributes of the index. T. Rowe Price compares the composition of the fund to that of the index. If a material misweighting develops, the portfolio manager seeks to rebalance the portfolio in an effort to realign it with its index.

The fund attempts to track the investment return of small- and mid-cap U.S. stocks by tracking the performance of its benchmark index, the S&P Completion Index (S&P Index). The S&P Index is a sub-index of the S&P Total Market Index and consists of all constituents in the S&P Total Market Index that are not also constituents of the S&P 500. The S&P Index included 3,312 stocks as of December 31, 2020.

In an attempt to track the S&P Index, the adviser selects stocks based on industry, size, and other characteristics. For example, if technology stocks made up 15% of the S&P Index, the fund would invest approximately 15% of its assets in technology stocks with similar characteristics. Several factors are considered in selecting representative stocks, including historical price movement, market capitalization, transaction costs, and others.

Because the fund typically holds securities in proportion to their weight in the benchmark index, the fund intends to be diversified in approximately the same proportion as the index is diversified. The fund may become nondiversified, as defined under the Investment Company Act of 1940, solely as a result of changes in the composition of the index.

While most assets will be invested in common stocks, the fund may also purchase stock index futures contracts and exchange-traded funds. Futures and exchange-traded funds would typically be used to help realign the fund’s portfolio with its benchmark index, gain broad market or sector exposure, or 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. In addition, the fund lends its portfolio securities as a means of generating additional income.

While there is no guarantee, the correlation between the fund and its benchmark 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 price movements in the fund are unrelated to price movements in the index.

Principal Risks

As with any fund, there is no guarantee that the fund will achieve its objective(s). 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, which may be even greater during periods of market disruption or volatility, are summarized as follows:

Index investing 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.

SUMMARY 3

Tracking error The returns of the fund may deviate from 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. Increased tracking error could also result from changes in the composition of the index or the timing of purchases and redemptions of fund shares. The fund does not attempt to fully replicate its benchmark index, which increases the potential for the fund’s performance to deviate from that of its index.

Market conditions The value of the fund’s investments may decrease, sometimes rapidly or unexpectedly, due to factors affecting an issuer held by the fund, particular industries, or the overall securities markets. A variety of factors can increase the volatility of the fund’s holdings and markets generally, including political or regulatory developments, recessions, inflation, rapid interest rate changes, war or acts of terrorism, natural disasters, and outbreaks of infectious illnesses or other widespread public health issues such as the coronavirus pandemic and related governmental and public responses. Certain events may cause instability across global markets, including reduced liquidity and disruptions in trading markets, while some events may affect certain geographic regions, countries, sectors, and industries more significantly than others. Government intervention in markets may impact interest rates, market volatility, and security pricing. These adverse developments may cause broad declines in market value due to short-term market movements or for significantly longer periods during more prolonged market downturns.

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 and falling prices. The value of stocks held by the fund may decline due to general weakness or volatility in the stock markets in which the fund invests or because of factors that affect a particular company or industry.

Small- and mid-cap stocks Investments in securities issued by small-cap and mid-cap companies are likely to be more volatile than investments in securities issued by larger companies. Small and medium-sized companies often have less experienced management, narrower product lines, more limited financial resources, and less publicly available information than larger companies. In addition, smaller companies tend to be more sensitive to changes in overall economic conditions and their securities may have limited trading markets.

Futures The use of futures contracts potentially exposes the fund to greater volatility than directly purchasing securities in the index, including possible illiquidity of the futures markets, contract prices that can be volatile and imperfectly correlated to movements in underlying security values, and potential losses in excess of the fund’s initial investment.

Nondiversification The fund may become nondiversified due to the composition of its benchmark index, and thus invest a large percentage of its assets in securities issued by or representing a small number of issuers. As a result, the fund’s performance may be adversely affected; the fund’s shares may experience greater price volatility; and the fund may be more susceptible to the risks associated with these particular issuers or to a single economic, political, or regulatory occurrence affecting these issuers.

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Securities lending Securities lending involves the risk that the fund may lose money because the borrower of the loaned securities fails to return the securities to the fund in a timely manner or at all. The fund may also lose money if there is a decline in the value of the collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. In addition, securities lending activities may cause adverse tax consequences for the fund.

Exchange-traded funds The fund will bear its proportionate share of the fees and expenses of each exchange-traded fund in which it invests. An investment in an exchange-traded fund involves substantially the same risks as investing directly in the exchange-traded fund’s underlying assets, although an exchange-traded fund may trade at a premium or discount to the actual net asset value of its portfolio securities, may have greater price volatility than its underlying assets, and its shares may have lower overall liquidity.

Cybersecurity breaches The fund could be harmed by intentional cyberattacks and other cybersecurity breaches, including unauthorized access to the fund’s assets, customer data and confidential shareholder information, or other proprietary information. In addition, a cybersecurity breach could cause one of the fund’s service providers or financial intermediaries to suffer unauthorized data access, data corruption, or loss of operational functionality.

Performance

The following performance information provides some indication of the risks of investing in the fund. The fund’s performance information represents only past performance (before and after taxes) and is not necessarily an indication of future results.

The following bar chart illustrates how much returns can differ from year to year by showing calendar year returns and the best and worst calendar quarter returns during those years for the fund.

EXTENDED EQUITY MARKET INDEX FUND

Calendar Year Returns

	Quarter Ended	Total Return		Quarter Ended	Total Return
Best Quarter	6/30/20	30.39%	Worst Quarter	3/31/20	-27.90%

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The following table shows the average annual total returns for the fund, and also compares the returns with the returns of a relevant broad-based market index, as well as with the returns of one or more comparative indexes that have investment characteristics similar to those of the fund, if applicable.

In addition, the table shows hypothetical after-tax returns to demonstrate 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 an IRA.

Average Annual Total Returns
			Periods ended
			December 31, 2020
									Inception
			1 Year		5 Years		10 Years		date
	Extended Equity Market Index Fund								01/30/1998
		Returns before taxes	30.82	%	15.60	%	13.05	%
		Returns after taxes on distributions	29.88		14.16		11.91
		Returns after taxes on distributions and sale of fund shares	18.87		12.15		10.52
	S&P Completion Index (reflects no deduction for fees, expenses, or taxes)
			32.17		15.93		13.12

Updated performance information is available through troweprice.com.

Management

Investment Adviser T. Rowe Price Associates, Inc. (T. Rowe Price or Price Associates)

Portfolio Manager	Title	Managed Fund Since	Joined Investment Adviser
Alexa M. Gagliardi	Chair of Investment Advisory Committee	2019	2014

Purchase and Sale of Fund Shares

The fund generally requires a $2,500 minimum initial investment ($1,000 minimum initial investment if opening an IRA, a custodial account for a minor, or a small business retirement plan account). Additional purchases generally require a $100 minimum. These investment minimums generally are waived for financial intermediaries and certain employer-sponsored retirement plans submitting orders on behalf of their customers.

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For investors holding shares of the fund directly with T. Rowe Price, you may purchase, redeem, or exchange fund shares by mail; by telephone (1-800-225-5132 for IRAs and nonretirement accounts; 1-800-492-7670 for small business retirement plans; and 1-800-638-8790 for institutional investors and financial intermediaries); or, for certain accounts, by accessing your account online through troweprice.com.

If you hold shares through a financial intermediary or retirement plan, you must purchase, redeem, and exchange shares of the fund through your intermediary or retirement plan. You should check with your intermediary or retirement plan to determine the investment minimums that apply to your account.

Tax Information

Any dividends or capital gains are declared and paid annually, usually in December. Redemptions or exchanges of fund shares and distributions by the fund, whether or not you reinvest these amounts in additional fund shares, generally may be taxed as ordinary income or capital gains unless you invest through a tax-deferred account (in which case you will be taxed upon withdrawal from such account).

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase shares of the fund through a broker-dealer or other financial intermediary (such as a bank), the fund and its related companies may pay the intermediary for the sale of fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

T. Rowe Price Associates, Inc. 100 East Pratt Street Baltimore, MD 21202	F124-045 5/1/21