Fund Summary

Investment Objective

The Fund seeks to provide long-term capital appreciation.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold Investor Shares or Admiral Shares of the Fund.

Shareholder Fees

(Fees paid directly from your investment)

	Investor Shares	Admiral Shares
Sales Charge (Load) Imposed on Purchases	None	None
Purchase Fee	None	None
Sales Charge (Load) Imposed on Reinvested Dividends	None	None
Redemption Fee	None	None
Account Service Fee (for certain fund account balances below	$20/year	$20/year
$10,000)
Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
	Investor Shares	Admiral Shares
Management Fees	0.37%	0.31%
12b-1 Distribution Fee	None	None
Other Expenses	0.01%	None
Total Annual Fund Operating Expenses	0.38%	0.31%

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Examples

The following examples are intended to help you compare the cost of investing in the Fund's Investor Shares or Admiral Shares with the cost of investing in other mutual funds. They illustrate the hypothetical expenses that you would incur over various periods if you were to invest $10,000 in the Fund's shares. These examples assume that the shares provide a return of 5% each year and that total annual fund operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you were to redeem your investment at the end of the given period. 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
Investor Shares	$39	$122	$213	$480
Admiral Shares	$32	$100	$174	$393

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 more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense examples, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 5% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests in stocks considered to have above-average earnings growth potential that is not reflected in their current market prices. The Fund's portfolio consists predominantly of large- and mid-capitalization stocks.

Principal Risks

An investment in the Fund could lose money over short or long periods of time. You should expect the Fund's share price and total return to fluctuate within a wide range. The Fund is subject to the following risks, which could affect the Fund's performance:

•Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.

•Asset concentration risk, which is the chance that, because the Fund tends to invest a high percentage of assets in its ten largest holdings, the Fund's performance may be hurt disproportionately by the poor performance of relatively few stocks.

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•Investment style risk, which is the chance that returns from large- and mid- capitalization growth stocks will trail returns from the overall stock market. Large- and mid-cap stocks each tend to go through cycles of doing better—or worse—than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years. Historically, mid-cap stocks have been more volatile in price than large-cap stocks.

•Manager risk, which is the chance that poor security selection will cause the Fund to underperform relevant benchmarks or other funds with a similar investment objective. In addition, significant investments in the health care and information technology sectors subject the Fund to proportionately higher exposure to the risks of these sectors.

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.

Annual Total Returns

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund's Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of a relevant market index, which has investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

Annual Total Returns — Vanguard PRIMECAP Fund Investor Shares

	2010		2011		2012		2013		2014		2015		2016		2017		2018		2019
60%							39.73
40%															29.51				27.78
	12.89				15.27				18.72
20%											2.58		10.63
0%
				-1.84														-2.01
-20%
-40%

During the periods shown in the bar chart, the highest return for a calendar quarter was 14.16% (quarter ended March 31, 2013), and the lowest return for a quarter was –15.78% (quarter ended September 30, 2011).

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Average Annual Total Returns for Periods Ended December 31, 2019

	1 Year	5 Years	10 Years
Vanguard PRIMECAP Fund Investor Shares
Return Before Taxes	27.78%	12.98%	14.58%
Return After Taxes on Distributions	25.74	11.37	13.31
Return After Taxes on Distributions and Sale of Fund Shares	17.89	10.10	12.00
Vanguard PRIMECAP Fund Admiral Shares
Return Before Taxes	27.88%	13.05%	14.67%
Standard & Poor's 500 Index
(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%

Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are shown only for the Investor Shares and may differ for each share class. After-tax returns are not relevant for a shareholder who holds fund shares in a tax- deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

Investment Advisor

PRIMECAP Management Company (PRIMECAP)

Portfolio Managers

Theo A. Kolokotrones, Chairman of PRIMECAP. He has co-managed the Fund since 1985.

Joel P. Fried, President of PRIMECAP. He has co-managed the Fund since 1988.

Alfred W. Mordecai, Vice Chairman of PRIMECAP. He has co-managed the Fund since 1999.

M. Mohsin Ansari, Executive Vice President of PRIMECAP. He has co-managed the Fund since 2007.

James Marchetti, Executive Vice President of PRIMECAP. He has co-managed the Fund since 2015.

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Purchase and Sale of Fund Shares

You may purchase or redeem shares online through our website (vanguard.com), by mail (The Vanguard Group, P.O. Box 1110, Valley Forge, PA 19482-1110), or by telephone (800-662-2739). The minimum investment amount required to open and maintain a Fund account for Investor Shares or Admiral Shares is $3,000 or $50,000, respectively. The minimum investment amount required to add to an existing Fund account is generally $1. Financial intermediaries, institutional clients, and Vanguard-advised clients should contact Vanguard for information on special eligibility rules that may apply to them regarding Admiral Shares. If you are investing through an intermediary, please contact that firm directly for more information regarding your eligibility. If you are investing through an employer-sponsored retirement or savings plan, your plan administrator or your benefits office can provide you with detailed information on how you can invest through your plan.

Tax Information

The Fund's distributions may be taxable as ordinary income or capital gain. If you are investing through a tax-advantaged account, such as an IRA or an employer- sponsored retirement or savings plan, special tax rules apply.

Payments to Financial Intermediaries

The Fund and its investment advisor do not pay financial intermediaries for sales of Fund shares.

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More on the Fund

This prospectus describes the principal risks you would face as a Fund shareholder. It is important to keep in mind one of the main principles of investing: generally, the higher the risk of losing money, the higher the potential reward. The reverse, also, is generally true: the lower the risk, the lower the potential reward. As you consider an investment in any mutual fund, you should take into account your personal tolerance

for fluctuations in the securities markets. Look for this symbol throughout the prospectus. It is used to mark detailed information about the more significant risks that you would confront as a Fund shareholder. To highlight terms and concepts important to mutual fund investors, we have provided Plain Talk® explanations along the way. Reading the prospectus will help you decide whether the Fund is the right investment for you. We suggest that you keep this prospectus for future reference.

Share Class Overview

The Fund offers two separate classes of shares: Investor Shares and Admiral Shares.

Both share classes offered by the Fund have the same investment objective, strategies, and policies. However, different share classes have different expenses; as a result, their investment returns will differ.

Plain Talk About Fund Expenses

All mutual funds have operating expenses. These expenses, which are deducted from a fund's gross income, are expressed as a percentage of the net assets of the fund. Assuming that operating expenses remain as stated in the Fees and Expenses section, Vanguard PRIMECAP Fund's expense ratios would be as follows: for Investor Shares, 0.38%, or $3.80 per $1,000 of average net assets; for Admiral Shares, 0.31%, or $3.10 per $1,000 of average net assets. The average expense ratio for multi-cap growth funds in 2018 was 1.15%, or $11.50 per $1,000 of average net assets (derived from data provided by Lipper, a Thomson Reuters Company, which reports on the mutual fund industry).

Plain Talk About Costs of Investing

Costs are an important consideration in choosing a mutual fund. That is because you, as a shareholder, pay a proportionate share of the costs of operating a fund and any transaction costs incurred when the fund buys or sells securities. These costs can erode a substantial portion of the gross income or the capital appreciation a fund achieves. Even seemingly small differences in expenses can, over time, have a dramatic effect on a fund's performance.

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The following sections explain the principal investment strategies and policies that the Fund uses in pursuit of its objective. The Fund's board of trustees, which oversees the Fund's management, may change investment strategies or policies in the interest of shareholders without a shareholder vote, unless those strategies or policies are designated as fundamental.

Market Exposure

The Fund invests mainly in common stocks of companies that the advisor believes have favorable prospects for capital appreciation and that sell at attractive prices but typically produce little current income. The Fund's portfolio consists predominantly of large- and mid-capitalization stocks.

Stocks of publicly traded companies are often classified according to market capitalization, which is the market value of a company's outstanding shares. These classifications typically include small-cap, mid-cap, and large-cap. It is important to understand that there are no "official" definitions of small-, mid-, and large-cap, even among Vanguard fund advisors, and that market capitalization ranges can change over time. The asset-weighted median market capitalization of the Fund's stock holdings as of September 30, 2019, was $102.88 billion.

The Fund is subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.

The Fund is subject to asset concentration risk, which is the chance that, because the Fund tends to invest a high percentage of assets in its ten largest holdings, the Fund's performance may be hurt disproportionately by the poor performance of relatively few stocks.

Growth stocks, which are the Fund's primary investments, are likely to be even more volatile in price than the stock market as a whole. Historically, growth funds have tended to outperform in bull markets and underperform in declining markets. Of course, there is no guarantee that this pattern will continue in the future. The Fund also holds a significant number of mid-cap stocks, which tend to be more volatile than the broader markets.

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The Fund is subject to investment style risk, which is the chance that returns from large- and mid-capitalization growth stocks will trail returns from the overall stock market. Large- and mid-cap stocks each tend to go through cycles of doing better—or worse—than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years. Historically, mid-cap stocks have been more volatile in price than large-cap stocks. The stock prices of mid-size companies tend to experience greater volatility because, among other things, mid-size companies tend to be more sensitive to changing economic conditions.

Plain Talk About Growth Funds and Value Funds

Growth investing and value investing are two styles employed by stock-fund managers. Growth funds generally invest in stocks of companies believed to have above-average potential for growth in revenue, earnings, cash flow, or other similar criteria. These stocks typically have low dividend yields, if any, and above- average prices in relation to measures such as earnings and book value. Value funds typically invest in stocks whose prices are below average in relation to those measures; these stocks often have above-average dividend yields. Value stocks also may remain undervalued by the market for long periods of time. Growth and value stocks have historically produced similar long-term returns, though each category has periods when it outperforms the other.

Security Selection

PRIMECAP, advisor to the Fund, selects common stocks that it believes have above- average earnings growth potential that is not reflected in the current market price. Companies selected for stock purchases typically have strong positions within their industries, increasing sales, improving profitability, good long-term prospects for above-average growth in earnings, and strong management teams.

Using careful analysis, the advisor attempts to quantify a company's "fundamental value," which is the advisor's estimate of the financial value of the company. The advisor compares the fundamental value with the market price of the company's stock. The advisor then decides whether to purchase the stock mainly on the basis of how attractive its market price is in relation to its fundamental value. Although the Fund invests with a long-term horizon of three to five years, the advisor may sell a stock if its market price appears to have risen above its fundamental value, if other securities appear to be more favorably priced, or if the reasons for which the stock was purchased no longer hold true.

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PRIMECAP does not try to make investment decisions based on short-term trends in the stock market. If attractively priced stocks cannot be found, the Fund's cash levels will increase.

Because PRIMECAP's selections are determined by an analysis of each individual stock, the Fund's makeup may differ substantially from the overall market's characteristics. For example, the proportion of the Fund's assets invested in a particular industry may be significantly larger or smaller than that industry's representation in the overall stock market.

The Fund is subject to manager risk, which is the chance that poor security selection will cause the Fund to underperform relevant benchmarks or other funds with a similar investment objective. In addition, significant investments in the health care and information technology sectors subject the Fund to proportionately higher exposure to the risks of these sectors.

The health care sector could be adversely affected by patent protection, government regulation, research and development costs, litigation, and competitive forces. The information technology sector could be adversely affected by overall economic conditions, short product cycles, rapid obsolescence of products, competition, and government regulation. These sectors could also be affected by other economic and non-economic factors, including those affecting the economy as a whole or the countries or regions where the companies in which the Fund invests operate.

Other Investment Policies and Risks

In addition to investing in stocks considered by the advisor to have above-average earnings growth potential, the Fund may make other kinds of investments to achieve its objective.

The Fund may invest a limited portion, up to 25%, of its assets in foreign securities, which may include depositary receipts. Foreign securities may be traded on U.S. or foreign markets. To the extent that it owns foreign securities, the Fund is subject to country risk and currency risk. Country risk is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value of securities issued by companies in foreign countries. In addition, the prices of foreign stocks and the prices of U.S. stocks have, at times, moved in opposite directions. Currency risk is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates.

The Fund may invest, to a limited extent, in derivatives. Generally speaking, a derivative is a financial contract whose value is based on the value of a financial asset (such as a stock, a bond, or a currency), a physical asset (such as gold, oil, or wheat), a

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market index, or a reference rate. Investments in derivatives may subject the Fund to risks different from, and possibly greater than, those of investments directly in the underlying securities or assets. The Fund will not use derivatives for speculation or for the purpose of leveraging (magnifying) investment returns.

The Fund may enter into foreign currency exchange forward contracts, which are a type of derivative. A foreign currency exchange forward contract is an agreement to buy or sell a currency at a specific price on a specific date, usually 30, 60, or 90 days in the future. In other words, the contract guarantees an exchange rate on a given date. Advisors of funds that invest in foreign securities can use these contracts to guard against unfavorable changes in currency exchange rates. These contracts, however, would not prevent the Fund's securities from falling in value as a result of risks other than unfavorable currency exchange movements.

Cash Management

The Fund's daily cash balance may be invested in Vanguard Market Liquidity Fund and/or Vanguard Municipal Cash Management Fund (each, a CMT Fund), which are low-cost money market funds. When investing in a CMT Fund, the Fund bears its proportionate share of the expenses of the CMT Fund in which it invests. Vanguard receives no additional revenue from Fund assets invested in a CMT Fund.

Methods Used to Meet Redemption Requests

Under normal circumstances, the Fund typically expects to meet redemptions with positive cash flows. When this is not an option, the Fund seeks to maintain its risk exposure by selling a cross section of the Fund's holdings to meet redemptions, while also factoring in transaction costs. Additionally, the Fund may work with larger clients to implement their redemptions in a manner that is least disruptive to the portfolio; see "Potentially disruptive redemptions" under Redeeming Shares in the Investing With Vanguard section.

Under certain circumstances, including under stressed market conditions, there are additional tools that the Fund may use in order to meet redemptions, including advancing the settlement of market trades with counterparties to match investor redemption payments or delaying settlement of an investor's transaction to match trade settlement within regulatory requirements. The Fund may also suspend payment of redemption proceeds for up to seven days; see "Emergency circumstances" under Redeeming Shares in the Investing With Vanguard section. Additionally under these unusual circumstances, the Fund may borrow money (subject to certain regulatory conditions and if available under board-approved procedures) through an interfund lending facility or through a bank line-of-credit, including a joint committed credit facility, in order to meet redemption requests.

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Temporary Investment Measures

The Fund may temporarily depart from its normal investment policies and strategies when the advisor believes that doing so is in the Fund's best interest, so long as the strategy or policy employed is consistent with the Fund's investment objective. For instance, the Fund may invest beyond its normal limits in derivatives or exchange- traded funds that are consistent with the Fund's investment objective when those instruments are more favorably priced or provide needed liquidity, as might be the case if the Fund is transitioning assets from one advisor to another or receives large cash flows that it cannot prudently invest immediately.

In addition, the Fund may take temporary defensive positions that are inconsistent with its normal investment policies and strategies—for instance, by allocating substantial assets to cash equivalent investments or other less volatile instruments— in response to adverse or unusual market, economic, political, or other conditions. In doing so, the Fund may succeed in avoiding losses but may otherwise fail to achieve its investment objective.

Frequent Trading or Market-Timing

Background. Some investors try to profit from strategies involving frequent trading of mutual fund shares, such as market-timing. For funds holding foreign securities, investors may try to take advantage of an anticipated difference between the price of the fund's shares and price movements in overseas markets, a practice also known as time-zone arbitrage. Investors also may try to engage in frequent trading of funds holding investments such as small-cap stocks and high-yield bonds. As money is shifted into and out of a fund by a shareholder engaging in frequent trading, the fund incurs costs for buying and selling securities, resulting in increased brokerage and administrative costs. These costs are borne by all fund shareholders, including the long-term investors who do not generate the costs. In addition, frequent trading may interfere with an advisor's ability to efficiently manage the fund.

Policies to address frequent trading. The Vanguard funds (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation- Protected Securities Index Fund) do not knowingly accommodate frequent trading. The board of trustees of each Vanguard fund (other than money market funds and short- term bond funds, but including Vanguard Short-Term Inflation-Protected Securities Index Fund) has adopted policies and procedures reasonably designed to detect and discourage frequent trading and, in some cases, to compensate the fund for the costs associated with it. These policies and procedures do not apply to ETF Shares because frequent trading in ETF Shares generally does not disrupt portfolio management or otherwise harm fund shareholders. Although there is no assurance that Vanguard will

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be able to detect or prevent frequent trading or market-timing in all circumstances, the following policies have been adopted to address these issues:

•Each Vanguard fund reserves the right to reject any purchase request—including exchanges from other Vanguard funds—without notice and regardless of size. For example, a purchase request could be rejected because the investor has a history of frequent trading or if Vanguard determines that such purchase may negatively affect a fund's operation or performance.

•Each Vanguard fund (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation-Protected Securities Index Fund) generally prohibits, except as otherwise noted in the Investing With Vanguard section, an investor's purchases or exchanges into a fund account for 30 calendar days after the investor has redeemed or exchanged out of that fund account.

•Certain Vanguard funds charge shareholders purchase and/or redemption fees on transactions.

See the Investing With Vanguard section of this prospectus for further details on Vanguard's transaction policies.

Each Vanguard fund (other than retail and government money market funds), in determining its net asset value, will use fair-value pricing when appropriate, as described in the Share Price section. Fair-value pricing may reduce or eliminate the profitability of certain frequent-trading strategies.

Do not invest with Vanguard if you are a market-timer.

Turnover Rate

Although the Fund generally seeks to invest for the long term, it may sell securities regardless of how long they have been held. The Financial Highlights section of this prospectus shows historical turnover rates for the Fund. A turnover rate of 100%, for example, would mean that the Fund had sold and replaced securities valued at 100% of its net assets within a one-year period. In general, the greater the turnover rate, the greater the impact transaction costs will have on a fund's return. Also, funds with high turnover rates may be more likely to generate capital gains, including short-term capital gains, that must be distributed to shareholders and will be taxable to shareholders investing through a taxable account.

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The Fund and Vanguard

The Fund is a member of The Vanguard Group, a family of over 200 funds. All of the funds that are members of The Vanguard Group (other than funds of funds) share in the expenses associated with administrative services and business operations, such as personnel, office space, and equipment.

Vanguard Marketing Corporation provides marketing services to the funds. Although fund shareholders do not pay sales commissions or 12b-1 distribution fees, each fund (other than a fund of funds) or each share class of a fund (in the case of a fund with multiple share classes) pays its allocated share of the Vanguard funds' marketing costs.

Plain Talk About Vanguard's Unique Corporate Structure

The Vanguard Group is owned jointly by the funds it oversees and thus indirectly by the shareholders in those funds. Most other mutual funds are operated by management companies that are owned by third parties—either public or private stockholders—and not by the funds they serve.

Investment Advisor

PRIMECAP Management Company, 177 East Colorado Blvd., 11th Floor, Pasadena, CA 91105, advisor to the Fund, is an investment advisory firm founded in 1983. PRIMECAP also provides investment advisory services to endowment funds, employee benefit plans, mutual funds, foundations, and other institutional clients unrelated to Vanguard. As of September 30, 2019, PRIMECAP managed approximately $136 billion in assets. The firm manages the Fund subject to the supervision and oversight of the trustees and officers of the Fund.

The Fund pays the advisor a fee, which is paid quarterly and is a percentage of average daily net assets under management during the most recent fiscal quarter. The fee has breakpoints, which means that the percentage declines as assets go up.

For the fiscal year ended September 30, 2019, the advisory fee represented an effective annual rate of 0.18% of the Fund's average net assets.

Under the terms of an SEC exemption, the Fund's board of trustees may, without prior approval from shareholders, change the terms of an advisory agreement with a third- party investment advisor or hire a new third-party investment advisor—either as a replacement for an existing advisor or as an additional advisor. Any significant change in the Fund's advisory arrangements will be communicated to shareholders in writing. As the Fund's sponsor and overall manager, The Vanguard Group, Inc. (Vanguard) may provide investment advisory services to the Fund at any time. Vanguard may also

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recommend to the board of trustees that an advisor be hired, terminated, or replaced or that the terms of an existing advisory agreement be revised. The Fund has filed an application seeking a similar SEC exemption with respect to investment advisors that are wholly owned subsidiaries of Vanguard. If the exemption is granted, the Fund may rely on the new SEC relief.

For a discussion of why the board of trustees approved the Fund's investment advisory agreement, see the most recent annual report to shareholders covering the fiscal year ended September 30.

The managers primarily responsible for the day-to-day management of the Fund are:

Theo A. Kolokotrones, Chairman of PRIMECAP. He has worked in investment management since 1970, has managed assets since 1979, has been with PRIMECAP since 1983, and has co-managed the Fund since 1985. Education: B.A., University of Chicago; M.B.A., Harvard Business School.

Joel P. Fried, President of PRIMECAP. He has worked in investment management since 1985, has been with PRIMECAP since 1986, has managed assets since 1987, and has co-managed the Fund since 1988. Education: B.S., University of California, Los Angeles; M.B.A., Anderson Graduate School of Business, University of California, Los Angeles.

Alfred W. Mordecai, Vice Chairman of PRIMECAP. He has worked in investment management and has been with PRIMECAP since 1997, has managed assets since 1999, and has co-managed the Fund since 1999. Education: B.S.E., Duke University; M.E.A., Virginia Polytechnic Institute and State University; M.B.A., Harvard Business School.

M. Mohsin Ansari, Executive Vice President of PRIMECAP. He has worked in investment management and has been with PRIMECAP since 2000, has managed assets since 2007, and has co-managed the Fund since 2007. Education: B.A., Colgate University; B.S., Washington University; M.B.A., Harvard Business School.

James Marchetti, Executive Vice President of PRIMECAP. He has worked in investment management and has been with PRIMECAP since 2005, has managed assets since 2014, and has co-managed the Fund since 2015. Education: B.S., Massachusetts Institute of Technology; M.B.A., MIT Sloan School of Management.

Each of these five individuals manages a portion of the Fund autonomously; there is no decision-making by committee. A small portion of the Fund's assets is managed by individuals in PRIMECAP's research department.

The Fund's Statement of Additional Information provides information about each portfolio manager's compensation, other accounts under management, and ownership of shares of the Fund.

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Dividends, Capital Gains, and Taxes

Fund Distributions

The Fund distributes to shareholders virtually all of its net income (interest and dividends, less expenses) as well as any net short-term or long-term capital gains realized from the sale of its holdings. Income and capital gains distributions, if any, generally occur annually in December. In addition, the Fund may occasionally make a supplemental distribution at some other time during the year.

You can receive distributions of income or capital gains in cash, or you can have them automatically reinvested in more shares of the Fund. However, if you are investing through an employer-sponsored retirement or savings plan, your distributions will be automatically reinvested in additional Fund shares.

Plain Talk About Distributions

As a shareholder, you are entitled to your portion of a fund's income from interest and dividends as well as capital gains from the fund's sale of investments. Income consists of both the dividends that the fund earns from any stock holdings and the interest it receives from any money market and bond investments. Capital gains are realized whenever the fund sells securities for higher prices than it paid for them. These capital gains are either short-term or long-term, depending on whether the fund held the securities for one year or less or for more than one year.

Basic Tax Points

Investors in taxable accounts should be aware of the following basic federal income tax points:

•Distributions are taxable to you whether or not you reinvest these amounts in additional Fund shares.

•Distributions declared in December—if paid to you by the end of January—are taxable as if received in December.

•Any dividend distribution or short-term capital gains distribution that you receive is taxable to you as ordinary income. If you are an individual and meet certain holding- period requirements with respect to your Fund shares, you may be eligible for reduced tax rates on "qualified dividend income,"if any, distributed by the Fund.

•Any distribution of net long-term capital gains is taxable to you as long-term capital gains, no matter how long you have owned shares in the Fund.

•Capital gains distributions may vary considerably from year to year as a result of the Fund's normal investment activities and cash flows.

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•A sale or exchange of Fund shares is a taxable event. This means that you may have a capital gain to report as income, or a capital loss to report as a deduction, when you complete your tax return.

•Any conversion between classes of shares of the same fund is a nontaxable event. By contrast, an exchange between classes of shares of different funds is a taxable event.

•Vanguard (or your intermediary) will send you a statement each year showing the tax status of all of your distributions.

Individuals, trusts, and estates whose income exceeds certain threshold amounts are subject to a 3.8% Medicare contribution tax on "net investment income." Net investment income takes into account distributions paid by the Fund and capital gains from any sale or exchange of Fund shares.

Dividend distributions and capital gains distributions that you receive, as well as your gains or losses from any sale or exchange of Fund shares, may be subject to state and local income taxes.

This prospectus provides general tax information only. If you are investing through a tax-advantaged account, such as an IRA or an employer-sponsored retirement or savings plan, special tax rules apply. Please consult your tax advisor for detailed information about any tax consequences for you.

Plain Talk About Buying a Dividend

Unless you are a tax-exempt investor or investing through a tax-advantaged account (such as an IRA or an employer-sponsored retirement or savings plan), you should consider avoiding a purchase of fund shares shortly before the fund makes a distribution, because doing so can cost you money in taxes. This is known as "buying a dividend." For example: On December 15, you invest $5,000, buying 250 shares for $20 each. If the fund pays a distribution of $1 per share on December 16, its share price will drop to $19 (not counting market change). You still have only $5,000 (250 shares x $19 = $4,750 in share value, plus 250 shares x $1 = $250 in distributions), but you owe tax on the $250 distribution you received—even if you reinvest it in more shares. To avoid buying a dividend, check a fund's distribution schedule before you invest.

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General Information

Backup withholding. By law, Vanguard must withhold 24% of any taxable distributions or redemptions from your account if you do not:

•Provide your correct taxpayer identification number.

•Certify that the taxpayer identification number is correct.

•Confirm that you are not subject to backup withholding.

Similarly, Vanguard (or your intermediary) must withhold taxes from your account if the IRS instructs us to do so.

Foreign investors. Vanguard funds offered for sale in the United States (Vanguard U.S. funds), including the Fund offered in this prospectus, are not widely available outside the United States. Non-U.S. investors should be aware that U.S. withholding and estate taxes and certain U.S. tax reporting requirements may apply to any investments in Vanguard U.S. funds. Foreign investors should visit the non-U.S. investors page on our website at vanguard.com for information on Vanguard's non-U.S. products.

Invalid addresses. If a dividend distribution or capital gains distribution check mailed to your address of record is returned as undeliverable, Vanguard will automatically reinvest the distribution and all future distributions until you provide us with a valid mailing address. Reinvestments will receive the net asset value calculated on the date of the reinvestment.

Share Price

Share price, also known as net asset value (NAV), is calculated as of the close of regular trading on the New York Stock Exchange (NYSE), generally 4 p.m., Eastern time, on each day that the NYSE is open for business (a business day). In the rare event the NYSE experiences unanticipated disruptions and is unavailable at the close of the trading day, the Fund reserves the right to treat such day as a business day and calculate NAVs as of the close of regular trading on the Nasdaq (or another alternate exchange if the Nasdaq is unavailable, as determined at Vanguard's discretion), generally 4 p.m., Eastern time. Each share class has its own NAV, which is computed by dividing the total assets, minus liabilities, allocated to the share class by the number of Fund shares outstanding for that class. On U.S. holidays or other days when the NYSE is closed, the NAV is not calculated, and the Fund does not sell or redeem shares. However, on those days the value of the Fund's assets may be affected to the extent that the Fund holds securities that change in value on those days (such as foreign securities that trade on foreign markets that are open).

Stocks held by a Vanguard fund are valued at their market value when reliable market quotations are readily available from the principal exchange or market on which they are traded. Such securities are generally valued at their official closing price, the last

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reported sales price, or if there were no sales that day, the mean between the closing bid and asking prices. When a fund determines that market quotations either are not readily available or do not accurately reflect the value of a security, the security is priced at its fair value (the amount that the owner might reasonably expect to receive upon the current sale of the security).

The values of any foreign securities held by a fund are converted into U.S. dollars using an exchange rate obtained from an independent third party as of the close of regular trading on the NYSE. The values of any mutual fund shares, including institutional money market fund shares, held by a fund are based on the NAVs of the shares. The values of any ETF shares or closed-end fund shares held by a fund are based on the market value of the shares.

A fund also will use fair-value pricing if the value of a security it holds has been materially affected by events occurring before the fund's pricing time but after the close of the principal exchange or market on which the security is traded. This most commonly occurs with foreign securities, which may trade on foreign exchanges that close many hours before the fund's pricing time. Intervening events might be company-specific (e.g., earnings report, merger announcement) or country-specific or regional/global (e.g., natural disaster, economic or political news, act of terrorism, interest rate change). Intervening events include price movements in U.S. markets that exceed a specified threshold or that are otherwise deemed to affect the value of foreign securities.

Fair-value pricing may be used for domestic securities—for example, if (1) trading in a security is halted and does not resume before the fund's pricing time or a security does not trade in the course of a day and (2) the fund holds enough of the security that its price could affect the NAV.

Fair-value prices are determined by Vanguard according to procedures adopted by the board of trustees. When fair-value pricing is employed, the prices of securities used by a fund to calculate the NAV may differ from quoted or published prices for the same securities.

Vanguard fund share prices are published daily on our website at vanguard.com/prices.

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Financial Highlights

Financial highlights information is intended to help you understand a fund's performance for the past five years (or, if shorter, its period of operations). Certain information reflects financial results for a single fund share. Total return represents the rate that an investor would have earned or lost each period on an investment in a fund or share class (assuming reinvestment of all distributions). This information has been obtained from the financial statements audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, whose report, along with fund financial statements, is included in a fund's most recent annual report to shareholders. You may obtain a free copy of a fund's latest annual or semiannual report, which is available upon request.

PRIMECAP Fund Investor Shares

			Year Ended September 30,
For a Share Outstanding Throughout Each Period	2019	2018	2017	2016	2015
Net Asset Value, Beginning of Period	$147.61	$126.84	$107.60	$96.99	$104.16
Investment Operations
Net Investment Income	1.7151	1.4741	1.3981	1.401	1.329
Net Realized and Unrealized Gain (Loss)
on Investments	(6.495)	26.529	23.145	15.103	(1.631)
Total from Investment Operations	(4.780)	28.003	24.543	16.504	(.302)
Distributions
Dividends from Net Investment Income	(1.470)	(1.400)	(1.356)	(1.114)	(1.160)
Distributions from Realized Capital Gains	(8.240)	(5.833)	(3.947)	(4.780)	(5.708)
Total Distributions	(9.710)	(7.233)	(5.303)	(5.894)	(6.868)
Net Asset Value, End of Period	$133.12	$147.61	$126.84	$107.60	$96.99
Total Return2	–2.41%	22.86%	23.75%	17.40%	–0.76%
Ratios/Supplemental Data
Net Assets, End of Period (Millions)	$6,095	$7,126	$7,699	$7,588	$7,741
Ratio of Total Expenses to
Average Net Assets	0.38%	0.38%	0.39%	0.39%	0.40%
Ratio of Net Investment Income to
Average Net Assets	1.32%	1.08%	1.22%	1.37%	1.33%
Portfolio Turnover Rate	5%	8%	8%	6%	9%

1 Calculated based on average shares outstanding.

2 Total returns do not include account service fees that may have applied in the periods shown.

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PRIMECAP Fund Admiral Shares

			Year Ended September 30,
For a Share Outstanding Throughout Each Period	2019	2018	2017	2016	2015
Net Asset Value, Beginning of Period	$153.09	$131.45	$111.52	$100.53	$108.08
Investment Operations
Net Investment Income	1.8801	1.6221	1.5281	1.532	1.550
Net Realized and Unrealized Gain (Loss)
on Investments	(6.756)	27.508	23.981	15.645	(1.784)
Total from Investment Operations	(4.876)	29.130	25.509	17.177	(.234)
Distributions
Dividends from Net Investment Income	(1.647)	(1.444)	(1.491)	(1.236)	(1.403)
Distributions from Realized Capital Gains	(8.547)	(6.046)	(4.088)	(4.951)	(5.913)
Total Distributions	(10.194)	(7.490)	(5.579)	(6.187)	(7.316)
Net Asset Value, End of Period	$138.02	$153.09	$131.45	$111.52	$100.53
Total Return2	–2.34%	22.95%	23.83%	17.48%	–0.69%
Ratios/Supplemental Data
Net Assets, End of Period (Millions)	$57,177	$62,361	$50,615	$39,852	$34,773
Ratio of Total Expenses to
Average Net Assets	0.31%	0.31%	0.32%	0.33%	0.34%
Ratio of Net Investment Income to
Average Net Assets	1.39%	1.15%	1.29%	1.43%	1.39%
Portfolio Turnover Rate	5%	8%	8%	6%	9%

1 Calculated based on average shares outstanding.

2 Total returns do not include account service fees that may have applied in the periods shown.

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Investing With Vanguard

This section of the prospectus explains the basics of doing business with Vanguard. Vanguard fund shares can be held directly with Vanguard or indirectly through an intermediary, such as a bank, a broker, or an investment advisor. If you hold Vanguard fund shares directly with Vanguard, you should carefully read each topic within this section that pertains to your relationship with Vanguard. If you hold Vanguard fund shares indirectly through an intermediary (including shares held in a brokerage account through Vanguard Brokerage Services®), please see Investing With Vanguard Through Other Firms, and also refer to your account agreement with the intermediary for information about transacting in that account. If you hold Vanguard fund shares through an employer-sponsored retirement or savings plan, please see Employer-Sponsored Plans. Vanguard reserves the right to change the following policies without notice. Please call or check online for current information. See Contacting Vanguard.

For Vanguard fund shares held directly with Vanguard, each fund you hold in an account is a separate "fund account." For example, if you hold three funds in a nonretirement account titled in your own name, two funds in a nonretirement account titled jointly with your spouse, and one fund in an individual retirement account, you have six fund accounts—and this is true even if you hold the same fund in multiple accounts. Note that each reference to "you" in this prospectus applies to any one or more registered account owners or persons authorized to transact on your account.

Purchasing Shares

Vanguard reserves the right, without notice, to increase or decrease the minimum amount required to open, convert shares to, or maintain a fund account or to add to an existing fund account.

Investment minimums may differ for certain categories of investors.

Account Minimums for Investor Shares

To open and maintain an account. $3,000.

To add to an existing account. Generally $1.

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Account Minimums for Admiral Shares

To open and maintain an account. $50,000. If you request Admiral Shares when you open a new account but the investment amount does not meet the account minimum for Admiral Shares, your investment will be placed in Investor Shares of the Fund. Financial intermediaries, institutional clients, and Vanguard-advised clients should contact Vanguard for information on special eligibility rules that may apply to them regarding Admiral Shares. If you are investing through an intermediary, please contact that firm directly for more information regarding your eligibility.

To add to an existing account. Generally $1.

How to Initiate a Purchase Request

Be sure to check Exchanging Shares, Frequent-Trading Limitations, and Other Rules You Should Know before placing your purchase request.

Online. You may open certain types of accounts, request a purchase of shares, and request an exchange through our website or our mobile application if you are registered for online access.

By telephone. You may call Vanguard to begin the account registration process or request that the account-opening forms be sent to you. You may also call Vanguard to request a purchase of shares in your account or to request an exchange. See Contacting Vanguard.

By mail. You may send Vanguard your account registration form and check to open a new fund account. To add to an existing fund account, you may send your check with an Invest-by-Mail form (from a transaction confirmation or your account statement) or with a deposit slip (available online).

How to Pay for a Purchase

By electronic bank transfer. You may purchase shares of a Vanguard fund through an electronic transfer of money from a bank account. To establish the electronic bank transfer service on an account, you must designate the bank account online, complete a form, or fill out the appropriate section of your account registration form. After the service is set up on your account, you can purchase shares by electronic bank transfer on a regular schedule (Automatic Investment Plan) or upon request. Your purchase request can be initiated online (if you are registered for online access), by telephone, or by mail.

By wire. Wiring instructions vary for different types of purchases. Please call Vanguard for instructions and policies on purchasing shares by wire. See Contacting Vanguard.

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By check. You may make initial or additional purchases to your fund account by sending a check with a deposit slip or by utilizing our mobile application if you are registered for online access. Also see How to Initiate a Purchase Request. Make your check payable to Vanguard and include the appropriate fund number (e.g., Vanguard—xx). For a list of Fund numbers (for share classes in this prospectus), see Additional Information.

By exchange. You may purchase shares of a Vanguard fund using the proceeds from the simultaneous redemption of shares of another Vanguard fund. You may initiate an exchange online (if you are registered for online access), by telephone, or by mail with an exchange form. See Exchanging Shares.

Trade Date

The trade date for any purchase request received in good order will depend on the day and time Vanguard receives your request, the manner in which you are paying, and the type of fund you are purchasing. Your purchase will be executed using the NAV as calculated on the trade date. See Share Price.

For purchases by check into all funds other than money market funds and for purchases by exchange, wire, or electronic bank transfer into all funds: If the purchase request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date for the purchase will be the same day. If the purchase request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date for the purchase will be the next business day.

For purchases by check into money market funds: If the purchase request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date for the purchase will be the next business day. If the purchase request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date for the purchase will be the second business day following the day Vanguard receives the purchase request. Because money market instruments must be purchased with federal funds and it takes a money market mutual fund one business day to convert check proceeds into federal funds, the trade date for the purchase will be one business day later than for other funds.

If your purchase request is not accurate and complete, it may be rejected. See Other Rules You Should Know—Good Order.

For further information about purchase transactions, consult our website at vanguard.com or see Contacting Vanguard.

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Other Purchase Rules You Should Know

Admiral Shares. Admiral Shares generally are not available for SIMPLE IRAs and Vanguard Individual 401(k) Plans.

Check purchases. All purchase checks must be written in U.S. dollars, be drawn on a U.S. bank, and be accompanied by good order instructions. Vanguard does not accept cash, traveler's checks, starter checks, or money orders. In addition, Vanguard may refuse checks that are not made payable to Vanguard.

New accounts. We are required by law to obtain from you certain personal information that we will use to verify your identity. If you do not provide the information, we may not be able to open your account. If we are unable to verify your identity, Vanguard reserves the right, without notice, to close your account or take such other steps as we deem reasonable. Certain types of accounts may require additional documentation.

Refused or rejected purchase requests. Vanguard reserves the right to stop selling fund shares or to reject any purchase request at any time and without notice, including, but not limited to, purchases requested by exchange from another Vanguard fund. This also includes the right to reject any purchase request because the investor has a history of frequent trading or because the purchase may negatively affect a fund's operation or performance.

Large purchases. Call Vanguard before attempting to invest a large dollar amount.

No cancellations. Vanguard will not accept your request to cancel any purchase request once processing has begun. Please be careful when placing a purchase request.

Converting Shares

When a conversion occurs, you receive shares of one class in place of shares of another class of the same fund. At the time of conversion, the dollar value of the "new" shares you receive equals the dollar value of the "old" shares that were converted. In other words, the conversion has no effect on the value of your investment in the fund at the time of the conversion. However, the number of shares you own after the conversion may be greater than or less than the number of shares you owned before the conversion, depending on the NAVs of the two share classes.

Vanguard will not accept your request to cancel any self-directed conversion request once processing has begun. Please be careful when placing a conversion request.

A conversion between share classes of the same fund is a nontaxable event.

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Trade Date

The trade date for any conversion request received in good order will depend on the day and time Vanguard receives your request. Your conversion will be executed using the NAVs of the different share classes on the trade date. See Share Price.

For a conversion request received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date will be the same day. For a conversion request received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date will be the next business day. See Other Rules You Should Know.

Conversions From Investor Shares to Admiral Shares

Self-directed conversions. If your account balance in the Fund is at least $50,000, you may ask Vanguard to convert your Investor Shares to Admiral Shares. You may request a conversion through our website (if you are registered for online access), by telephone, or by mail. Financial intermediaries, institutional clients, and Vanguard- advised clients should contact Vanguard for information on special eligibility rules that may apply to them regarding Admiral Shares. See Contacting Vanguard. If you are investing through an intermediary, please contact that firm directly for more information regarding your eligibility.

Automatic conversions. Vanguard conducts periodic reviews of account balances and may, if your account balance in the Fund exceeds $50,000, automatically convert your Investor Shares to Admiral Shares. You will be notified before an automatic conversion occurs and will have an opportunity to instruct Vanguard not to effect the conversion.

Financial intermediaries, institutional clients, and Vanguard-advised clients should contact Vanguard for information on special eligibility rules that may apply to them regarding Admiral Shares. If you are investing through an intermediary, please contact that firm directly for more information regarding your eligibility.

Mandatory Conversions to Investor Shares

If an account no longer meets the balance requirements for Admiral Shares, Vanguard may automatically convert the shares in the account to Investor Shares. A decline in the account balance because of market movement may result in such a conversion. Vanguard will notify the investor in writing before any mandatory conversion occurs.

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Redeeming Shares

How to Initiate a Redemption Request

Be sure to check Exchanging Shares, Frequent-Trading Limitations, and Other Rules You Should Know before placing your redemption request.

Online. You may request a redemption of shares or request an exchange through our website or our mobile application if you are registered for online access.

By telephone. You may call Vanguard to request a redemption of shares or an exchange. See Contacting Vanguard.

By mail. You may send a form (available online) to Vanguard to redeem from a fund account or to make an exchange.

How to Receive Redemption Proceeds

By electronic bank transfer. You may have the proceeds of a fund redemption sent directly to a designated bank account. To establish the electronic bank transfer service on an account, you must designate a bank account online, complete a form, or fill out the appropriate section of your account registration form. After the service is set up on your account, you can redeem shares by electronic bank transfer on a regular schedule (Automatic Withdrawal Plan) or upon request. Your redemption request can be initiated online (if you are registered for online access), by telephone, or by mail.

By wire. To receive your proceeds by wire, you may instruct Vanguard to wire your redemption proceeds ($100 minimum) to a previously designated bank account. To establish the wire redemption service, you generally must designate a bank account online, complete a form, or fill out the appropriate section of your account registration form.

Please note that Vanguard charges a $10 wire fee for outgoing wire redemptions. The fee is assessed in addition to, rather than being withheld from, redemption proceeds and is paid directly to the fund in which you invest. For example, if you redeem $100 via a wire, you will receive the full $100, and the $10 fee will be assessed to your fund account through an additional redemption of fund shares. If you redeem your entire fund account, your redemption proceeds will be reduced by the amount of the fee. The wire fee does not apply to accounts held by Flagship and Flagship Select clients; accounts held through intermediaries, including Vanguard Brokerage Services; or accounts held by institutional clients.

By exchange. You may have the proceeds of a Vanguard fund redemption invested directly in shares of another Vanguard fund. You may initiate an exchange online (if you are registered for online access), by telephone, or by mail. See Exchanging Shares.

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By check. If you have not chosen another redemption method, Vanguard will mail you a redemption check, generally payable to all registered account owners, normally within two business days of your trade date, and generally to the address of record.

Trade Date

The trade date for any redemption request received in good order will depend on the day and time Vanguard receives your request and the manner in which you are redeeming. Your redemption will be executed using the NAV as calculated on the trade date. See Share Price.

For redemptions by check, exchange, or wire: If the redemption request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date will be the same day. If the redemption request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date will be the next business day.

•Note on timing of wire redemptions from money market funds: For telephone requests received by Vanguard on a business day before 10:45 a.m., Eastern time (2 p.m., Eastern time, for Vanguard Prime Money Market Fund; 12:30 p.m., Eastern time, for Vanguard Federal Money Market Fund), the redemption proceeds generally will leave Vanguard by the close of business the same day. For telephone requests received by Vanguard on a business day after those cut-off times, or on a nonbusiness day, and for all requests other than by telephone, the redemption proceeds generally will leave Vanguard by the close of business on the next business day.

•Note on timing of wire redemptions from all other funds: For requests received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the redemption proceeds generally will leave Vanguard by the close of business on the next business day. For requests received by Vanguard on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the redemption proceeds generally will leave Vanguard by the close of business on the second business day after Vanguard receives the request.

For redemptions by electronic bank transfer: If the redemption request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date will be the same day. If the redemption request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date will be the next business day.

If your redemption request is not accurate and complete, it may be rejected. If we are unable to send your redemption proceeds by wire or electronic bank transfer because the receiving institution rejects the transfer, Vanguard will make additional efforts to complete your transaction. If Vanguard is still unable to complete the transaction, we

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may send the proceeds of the redemption to you by check, generally payable to all registered account owners, or use your proceeds to purchase new shares of the fund from which you sold shares for the purpose of the wire or electronic bank transfer transaction. See Other Rules You Should Know—Good Order.

If your redemption request is received in good order, we typically expect that redemption proceeds will be paid by the Fund within one business day of the trade date; however, in certain circumstances, investors may experience a longer settlement period at the time of the transaction. For further information, see "Potentially disruptive redemptions" and "Emergency circumstances."

For further information about redemption transactions, consult our website at vanguard.com or see Contacting Vanguard.

Other Redemption Rules You Should Know

Documentation for certain accounts. Special documentation may be required to redeem from certain types of accounts, such as trust, corporate, nonprofit, or retirement accounts. Please call us before attempting to redeem from these types of accounts.

Potentially disruptive redemptions. Vanguard reserves the right to pay all or part of a redemption in kind—that is, in the form of securities—if we reasonably believe that a cash redemption would negatively affect the fund's operation or performance or that the shareholder may be engaged in market-timing or frequent trading. Under these circumstances, Vanguard also reserves the right to delay payment of the redemption proceeds for up to seven calendar days. By calling us before you attempt to redeem a large dollar amount, you may avoid in-kind or delayed payment of your redemption. Please see Frequent-Trading Limitations for information about Vanguard's policies to limit frequent trading.

Recently purchased shares. Although you can redeem shares at any time, proceeds may not be made available to you until the fund collects payment for your purchase. This may take up to seven calendar days for shares purchased by check or by electronic bank transfer. If you have written a check on a fund with checkwriting privileges, that check may be rejected if your fund account does not have a sufficient available balance.

Share certificates. Share certificates are no longer issued for Vanguard funds. Shares currently held in certificates cannot be redeemed, exchanged, converted, or transferred (reregistered) until you return the certificates (unsigned) to Vanguard by registered mail.

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Address change. If you change your address online or by telephone, there may be up to a 14-day restriction on your ability to request check redemptions online and by telephone. You can request a redemption in writing (using a form available online) at any time. Confirmations of address changes are sent to both the old and new addresses.

Payment to a different person or address. At your request, we can make your redemption check payable, or wire your redemption proceeds, to a different person or send it to a different address. However, this generally requires the written consent of all registered account owners and may require additional documentation, such as a signature guarantee or a notarized signature. You may obtain a signature guarantee from some commercial or savings banks, credit unions, trust companies, or member firms of a U.S. stock exchange.

No cancellations. Vanguard will not accept your request to cancel any redemption request once processing has begun. Please be careful when placing a redemption request.

Emergency circumstances. Vanguard funds can postpone payment of redemption proceeds for up to seven calendar days. In addition, Vanguard funds can suspend redemptions and/or postpone payments of redemption proceeds beyond seven calendar days at times when the NYSE is closed or during emergency circumstances, as determined by the SEC.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of one Vanguard fund to simultaneously purchase shares of a different Vanguard fund. You can make exchange requests online (if you are registered for online access), by telephone, or by mail. See Purchasing Shares and Redeeming Shares.

If the NYSE is open for regular trading (generally until 4 p.m., Eastern time, on a business day) at the time an exchange request is received in good order, the trade date generally will be the same day. See Other Rules You Should Know—Good Order for additional information on all transaction requests.

Vanguard will not accept your request to cancel any exchange request once processing has begun. Please be careful when placing an exchange request.

Call Vanguard before attempting to exchange a large dollar amount. By calling us before you attempt to exchange a large dollar amount, you may avoid delayed or rejected transactions.

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Please note that Vanguard reserves the right, without notice, to revise or terminate the exchange privilege, limit the amount of any exchange, or reject an exchange, at any time, for any reason. See Frequent-Trading Limitations for additional restrictions on exchanges.

Frequent-Trading Limitations

Because excessive transactions can disrupt management of a fund and increase the fund's costs for all shareholders, the board of trustees of each Vanguard fund places certain limits on frequent trading in the funds. Each Vanguard fund (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation- Protected Securities Index Fund) limits an investor's purchases or exchanges into a fund account for 30 calendar days after the investor has redeemed or exchanged out of that fund account. ETF Shares are not subject to these frequent-trading limits.

For Vanguard Retirement Investment Program pooled plans, the limitations apply to exchanges made online or by telephone.

These frequent-trading limitations do not apply to the following:

•Purchases of shares with reinvested dividend or capital gains distributions.

•Transactions through Vanguard's Automatic Investment Plan, Automatic Exchange Service, Direct Deposit Service, Automatic Withdrawal Plan, Required Minimum Distribution Service, and Vanguard Small Business Online®.

•Discretionary transactions through Vanguard Personal Advisor Services®, Vanguard Institutional Advisory Services®, and Vanguard Digital AdvisorTM.

•Redemptions of shares to pay fund or account fees.

•Redemptions of shares to remove excess shareholder contributions to certain types of retirement accounts (including, but not limited to, IRAs and Vanguard Individual 401(k) Plans).

•Transfers and reregistrations of shares within the same fund.

•Purchases of shares by asset transfer or direct rollover.

•Conversions of shares from one share class to another in the same fund.

•Checkwriting redemptions.

•Section 529 college savings plans.

•Certain approved institutional portfolios and asset allocation programs, as well as trades made by funds or trusts managed by Vanguard or its affiliates that invest in other Vanguard funds. (Please note that shareholders of Vanguard's funds of funds are subject to the limitations.)

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For participants in employer-sponsored defined contribution plans,* the frequent- trading limitations do not apply to:

•Purchases of shares with participant payroll or employer contributions or loan repayments.

•Purchases of shares with reinvested dividend or capital gains distributions.

•Distributions, loans, and in-service withdrawals from a plan.

•Redemptions of shares as part of a plan termination or at the direction of the plan.

•Transactions executed through the Vanguard Managed Account Program.

•Redemptions of shares to pay fund or account fees.

•Share or asset transfers or rollovers.

•Reregistrations of shares.

•Conversions of shares from one share class to another in the same fund.

•Exchange requests submitted by written request to Vanguard. (Exchange requests submitted by fax, if otherwise permitted, are subject to the limitations.)

*The following Vanguard fund accounts are subject to the frequent-trading limitations: SEP-IRAs, SIMPLE IRAs, certain Individual 403(b)(7) Custodial Accounts, and Vanguard Individual 401(k) Plans.

Accounts Held by Institutions (Other Than Defined Contribution Plans)

Vanguard will systematically monitor for frequent trading in institutional clients' accounts. If we detect suspicious trading activity, we will investigate and take appropriate action, which may include applying to a client's accounts the 30-day policy previously described, prohibiting a client's purchases of fund shares, and/or revoking the client's exchange privilege.

Accounts Held by Intermediaries

When intermediaries establish accounts in Vanguard funds for the benefit of their clients, we cannot always monitor the trading activity of the individual clients. However, we review trading activity at the intermediary (omnibus) level, and if we detect suspicious activity, we will investigate and take appropriate action. If necessary, Vanguard may prohibit additional purchases of fund shares by an intermediary, including for the benefit of certain of the intermediary's clients. Intermediaries also may monitor their clients' trading activities with respect to Vanguard funds.

For those Vanguard funds that charge purchase and/or redemption fees, intermediaries will be asked to assess these fees on client accounts and remit these fees to the funds. The application of purchase and redemption fees and frequent- trading limitations may vary among intermediaries. There are no assurances that

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Vanguard will successfully identify all intermediaries or that intermediaries will properly assess purchase and redemption fees or administer frequent-trading limitations. If you invest with Vanguard through an intermediary, please read that firm's materials carefully to learn of any other rules or fees that may apply.

Other Rules You Should Know

Prospectus and Shareholder Report Mailings

When two or more shareholders have the same last name and address, just one summary prospectus (or prospectus) and/or shareholder report may be sent in an attempt to eliminate the unnecessary expense of duplicate mailings. You may request individual prospectuses and reports by contacting our Client Services Department by telephone or online. See Contacting Vanguard.

Vanguard.com

Registration. If you are a registered user of vanguard.com, you can review your account holdings; buy, sell, or exchange shares of most Vanguard funds; and perform most other transactions through our website. You must register for this service online.

Electronic delivery. Vanguard can deliver your account statements, transaction confirmations, prospectuses, certain tax forms, and shareholder reports electronically. If you are a registered user of vanguard.com, you can consent to the electronic delivery of these documents by logging on and changing your mailing preferences under "Account Maintenance." You can revoke your electronic consent at any time through our website, and we will begin to send paper copies of these documents within 30 days of receiving your revocation.

Telephone Transactions

Automatic. When we set up your account, we will automatically enable you to do business with us by telephone, unless you instruct us otherwise in writing.

Tele-Account®. To obtain fund and account information through Vanguard's automated telephone service, you must first establish a Personal Identification Number (PIN) by calling Tele-Account at 800-662-6273.

32

Proof of a caller's authority. We reserve the right to refuse a telephone request if the caller is unable to provide the requested information or if we reasonably believe that the caller is not an individual authorized to act on the account. Before we allow a caller to act on an account, we may request the following information:

•Authorization to act on the account (as the account owner or by legal documentation or other means).

•Account registration and address.

•Fund name and account number, if applicable.

•Other information relating to the caller, the account owner, or the account.

Good Order

We reserve the right to reject any transaction instructions that are not in "good order." Good order generally means that your instructions:

•Are provided by the person(s) authorized in accordance with Vanguard's policies and procedures to access the account and request transactions.

•Include the fund name and account number.

•Include the amount of the transaction (stated in dollars, shares, or percentage). Written instructions also must generally be provided on a Vanguard form and include:

•Signature(s) and date from the authorized person(s).

•Signature guarantees or notarized signatures, if required for the type of transaction. (Call Vanguard for specific requirements.)

•Any supporting documentation that may be required.

Good order requirements may vary among types of accounts and transactions. For more information, consult our website at vanguard.com or see Contacting Vanguard.

Vanguard reserves the right, without notice, to revise the requirements for good order.

Future Trade-Date Requests

Vanguard does not accept requests to hold a purchase, conversion, redemption, or exchange transaction for a future date. All such requests will receive trade dates as previously described in Purchasing Shares, Converting Shares, Redeeming Shares, and Exchanging Shares. Vanguard reserves the right to return future-dated purchase checks.

Accounts With More Than One Owner

If an account has more than one owner or authorized person, Vanguard generally will accept instructions from any one owner or authorized person.

33

Responsibility for Fraud

You should take precautions to protect yourself from fraud. Keep your account-related information private, and review any account confirmations, statements, or other information that we provide to you as soon as you receive them. Let us know immediately if you discover unauthorized activity or see something on your account that you do not understand or that looks unusual.

Vanguard will not be responsible for losses that result from transactions by a person who we reasonably believe is authorized to act on your account.

Uncashed Checks

Please cash your distribution or redemption checks promptly. Vanguard will not pay interest on uncashed checks. Vanguard may be required to transfer assets related to uncashed checks to a state under the state's abandoned property law.

Dormant Accounts

If your account has no activity in it for a period of time, Vanguard may be required to transfer it to a state under the state's abandoned property law, subject to potential federal or state withholding taxes.

Unusual Circumstances

If you experience difficulty contacting Vanguard online or by telephone, you can send us your transaction request on a Vanguard form by regular or express mail.

Investing With Vanguard Through Other Firms

You may purchase or sell shares of most Vanguard funds through a financial intermediary, such as a bank, a broker, or an investment advisor. Please consult your financial intermediary to determine which, if any, shares are available through that firm and to learn about other rules that may apply. Your financial intermediary can provide you with account information and any required tax forms. You may be required to pay a commission on purchases of mutual fund shares made through a financial intermediary.

Please see Frequent-Trading Limitations—Accounts Held by Intermediaries for information about the assessment of any purchase or redemption fees and the monitoring of frequent trading for accounts held by intermediaries.

34

Account Service Fee

Vanguard may charge a $20 account service fee on fund accounts that have a balance below $10,000 for any reason, including market fluctuation. The account service fee applies to both retirement and nonretirement fund accounts and may be assessed on fund accounts in all Vanguard funds, regardless of the account minimum. The fee, which will be collected by redeeming fund shares in the amount of $20, will be deducted from fund accounts subject to the fee once per calendar year.

If you elect to receive your statements and other materials electronically (i.e., by e-delivery), the account service fee will not be charged, so long as your election remains in effect. You can make your e-delivery election on vanguard.com.

Beginning on January 1, 2021, you may elect to receive paper copies of shareholder reports free of charge as noted on the cover of this prospectus.

Certain account types have alternative fee structures, including SIMPLE IRAs, Vanguard Retirement Investment Program pooled plans, and Vanguard Individual 401(k) Plans.

Low-Balance Accounts

The Fund reserves the right to liquidate a fund account whose balance falls below the account minimum for any reason, including market fluctuation. This liquidation policy applies to nonretirement fund accounts and accounts that are held through intermediaries. Any such liquidation will be preceded by written notice to the investor.

Right to Change Policies

In addition to the rights expressly stated elsewhere in this prospectus, Vanguard reserves the right, without notice, to (1) alter, add, or discontinue any conditions of purchase (including eligibility requirements), redemption, exchange, conversion, service, or privilege at any time and (2) alter, impose, discontinue, or waive any purchase fee, redemption fee, account service fee, or other fee charged to a shareholder or a group of shareholders. Changes may affect any or all investors. These actions will be taken when, at the sole discretion of Vanguard management, Vanguard believes they are in the best interest of a fund.

Account Restrictions

Vanguard reserves the right to: (1) redeem all or a portion of a fund/account to meet a legal obligation, including tax withholding, tax lien, garnishment order, or other obligation imposed on your account by a court or government agency; (2) redeem shares, close an account, or suspend account privileges, features, or options in the case of threatening conduct or activity; (3) redeem shares, close an account, or suspend account privileges, features, or options if Vanguard believes or suspects that not doing so could result in a suspicious, fraudulent, or illegal transaction; (4) place restrictions on the ability to redeem any or all shares in an account if it is required to

35

do so by a court or government agency; (5) place restrictions on the ability to redeem any or all shares in an account if Vanguard believes that doing so will prevent fraud, financial exploitation or abuse, or to protect vulnerable investors; (6) freeze any account and/or suspend account services if Vanguard has received reasonable notice of a dispute regarding the assets in an account, including notice of a dispute between the registered or beneficial account owners; and (7) freeze any account and/or suspend account services upon initial notification to Vanguard of the death of an account owner.

Share Classes

Vanguard reserves the right, without notice, to change the eligibility requirements of its share classes, including the types of clients who are eligible to purchase each share class.

Fund and Account Updates

Confirmation Statements

We will send (or provide through our website, whichever you prefer) a confirmation of your trade date and the amount of your transaction when you buy, sell, exchange, or convert shares. However, we will not send confirmations reflecting only checkwriting redemptions or the reinvestment of dividend or capital gains distributions. For any month in which you had a checkwriting redemption, a Checkwriting Activity Statement will be sent to you itemizing the checkwriting redemptions for that month. Promptly review each confirmation statement that we provide to you. It is important that you contact Vanguard immediately with any questions you may have about any transaction reflected on a confirmation statement, or Vanguard will consider the transaction properly processed.

Portfolio Summaries

We will send (or provide through our website, whichever you prefer) quarterly portfolio summaries to help you keep track of your accounts throughout the year. Each summary shows the market value of your account at the close of the statement period, as well as all distributions, purchases, redemptions, exchanges, transfers, and conversions for the current calendar quarter (or month). Promptly review each summary that we provide to you. It is important that you contact Vanguard immediately with any questions you may have about any transaction reflected on the summary, or Vanguard will consider the transaction properly processed.

36

Tax Information Statements

For most accounts, Vanguard (or your intermediary) is required to provide annual tax forms to assist you in preparing your income tax returns. These forms are generally available for each calendar year early in the following year. Registered users of vanguard.com can also view certain forms through our website. Vanguard (or your intermediary) may also provide you with additional tax-related documentation. For more information, consult our website at vanguard.com or see Contacting Vanguard.

Annual and Semiannual Reports

We will send (or provide through our website, whichever you prefer) reports about Vanguard PRIMECAP Fund twice a year, in May and November. These reports include overviews of the financial markets and provide the following specific Fund information:

•Performance assessments and comparisons with industry benchmarks.

•Reports from the advisor.

•Financial statements with listings of Fund holdings.

Portfolio Holdings

Please consult the Fund's Statement of Additional Information or our website for a description of the policies and procedures that govern disclosure of the Fund's portfolio holdings.

Employer-Sponsored Plans

Your plan administrator or your employee benefits office can provide you with detailed information on how to participate in your plan and how to elect the Fund as an investment option.

•If you have any questions about the Fund or Vanguard, including those about the Fund's investment objective, strategies, or risks, contact Vanguard Participant Services toll-free at 800-523-1188 or visit our website at vanguard.com.

•If you have questions about your account, contact your plan administrator or the organization that provides recordkeeping services for your plan.

•Be sure to carefully read each topic that pertains to your transactions with Vanguard.

Vanguard reserves the right to change its policies without notice to shareholders.

37

Transactions

Processing times for your transaction requests may differ among recordkeepers or among transaction and funding types. Your plan's recordkeeper (which may also be Vanguard) will determine the necessary processing time frames for your transaction requests prior to submission to the Fund. Consult your recordkeeper or plan administrator for more information.

If Vanguard is serving as your plan recordkeeper and if your transaction involves one or more investments with an early cut-off time for processing or another trading restriction, your entire transaction will be subject to the restriction when the trade date for your transaction is determined.

Contacting Vanguard

Web

Vanguard.com	For the most complete source of Vanguard news
	For fund, account, and service information
	For most account transactions
	For literature requests
	24 hours a day, 7 days a week
Phone
Vanguard Tele-Account® 800-662-6273	For automated fund and account information
	Toll-free, 24 hours a day, 7 days a week

Client Services 800-662-2739	For account information
(Text telephone for people with hearing	For most account transactions
impairment at 800-749-7273)

Institutional Division	For information and services for large institutional investors
888-809-8102
Financial Advisor and Intermediary	For information and services for financial intermediaries
Sales Support 800-997-2798	including financial advisors, broker-dealers, trust institutions,
	and insurance companies
Financial Advisory and Intermediary	For account information and trading support for financial
Trading Support 800-669-0498	intermediaries including financial advisors, broker-dealers,
	trust institutions, and insurance companies

38

Additional Information

	Inception	Newspaper	Vanguard	CUSIP
	Date	Abbreviation	Fund Number	Number
PRIMECAP Fund
Investor Shares	11/1/1984	Prmcp	59	921936100
Admiral Shares	11/12/2001	PrmcpAdml	559	921936209

39

Glossary of Investment Terms

Capital Gains Distributions. Payments to mutual fund shareholders of gains realized on securities that a fund has sold at a profit, minus any realized losses.

Cash Equivalent Investments. Cash deposits, short-term bank deposits, and money market instruments that include U.S. Treasury bills and notes, bank certificates of deposit (CDs), repurchase agreements, commercial paper, and banker's acceptances.

Common Stock. A security representing ownership rights in a corporation.

Dividend Distributions. Payments to mutual fund shareholders of income from interest or dividends generated by a fund's investments.

Expense Ratio. A fund's total annual operating expenses expressed as a percentage of the fund's average net assets. The expense ratio includes management and administrative expenses, but it does not include the transaction costs of buying and selling portfolio securities.

Inception Date. The date on which the assets of a fund (or one of its share classes) are first invested in accordance with the fund's investment objective. For funds with a subscription period, the inception date is the day after that period ends. Investment performance is generally measured from the inception date.

Joint Committed Credit Facility. The Fund participates, along with other funds managed by Vanguard, in a committed credit facility provided by a syndicate of lenders pursuant to a credit agreement that may be renewed annually; each Vanguard fund is individually liable for its borrowings, if any, under the credit facility. The amount and terms of the committed credit facility are subject to approval by the Fund's board of trustees and renegotiation with the lender syndicate on an annual basis.

Median Market Capitalization. An indicator of the size of companies in which a fund invests; the midpoint of market capitalization (market price x shares outstanding) of a fund's stocks, weighted by the proportion of the fund's assets invested in each stock. Stocks representing half of the fund's assets have market capitalizations above the median, and the rest are below it.

Mutual Fund. An investment company that pools the money of many people and invests it in a variety of securities in an effort to achieve a specific objective over time.

New York Stock Exchange (NYSE). A stock exchange based in New York City that is open for regular trading on business days, Monday through Friday, from 9:30 a.m. to 4 p.m., Eastern time.

Securities. Stocks, bonds, money market instruments, and other investments.

40

Standard & Poor's 500 Index. A widely recognized benchmark of U.S. stock market performance that is dominated by the stocks of large U.S. companies.

Total Return. A percentage change, over a specified time period, in a mutual fund's net asset value, assuming the reinvestment of all distributions of dividends and capital gains.

Volatility. The fluctuations in value of a mutual fund or other security. The greater a fund's volatility, the wider the fluctuations in its returns.

Yield. Income (interest or dividends) earned by an investment, expressed as a percentage of the investment's price.

41

 

P.O. Box 2600

Valley Forge, PA 19482-2600

Connect with Vanguard® > vanguard.com

P 059 012020

 

Vanguard Target Retirement Income Fund

Investment Objective

The Fund seeks to provide current income and some capital appreciation.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund.

Shareholder Fees

(Fees paid directly from your investment)

Sales Charge (Load) Imposed on Purchases	None
Purchase Fee	None
Sales Charge (Load) Imposed on Reinvested Dividends	None
Redemption Fee	None
Account Service Fee (for certain fund account balances below $10,000)	$20/year
Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
Management Fees	None
12b-1 Distribution Fee	None
Other Expenses	None
Acquired Fund Fees and Expenses	0.12%
Total Annual Fund Operating Expenses	0.12%

1

Example

The following example is intended to help you compare the cost of investing in the Fund (based on the fees and expenses of the acquired funds) with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you were to invest $10,000 in the Fund's shares. This example assumes that the Fund provides a return of 5% each year and that total annual fund operating expenses of the Fund (and its underlying funds) remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you were to redeem your investment at the end of the given period. 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
$12	$39	$68	$154

Portfolio Turnover

The Fund may pay transaction costs, such as purchase fees, 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 more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 10% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests in other Vanguard mutual funds (underlying funds) according to an asset allocation strategy designed for investors currently in retirement. As of September 30, 2019, the Fund's asset allocation among the underlying funds was as follows:

•	Vanguard Total Bond Market II Index Fund	37.1%
• Vanguard Total Stock Market Index Fund		18.3%
•	Vanguard Short-Term Inflation-Protected Securities Index Fund	16.6%
•	Vanguard Total International Bond Index Fund	16.1%
•	Vanguard Total International Stock Index Fund	11.9%

At any given time, the Fund's asset allocation may be affected by a variety of factors, such as whether the underlying funds are accepting additional investments.

2

The Fund's indirect bond holdings are a diversified mix of short-, intermediate-, and long- term U.S. government, U.S. agency, and investment-grade U.S. corporate bonds; inflation-protected public obligations issued by the U.S. Treasury; mortgage-backed and asset-backed securities; and government, agency, corporate, and securitized investment- grade foreign bonds issued in currencies other than the U.S. dollar (but hedged by Vanguard to minimize foreign currency exposure).

The Fund's indirect stock holdings are a diversified mix of U.S. and foreign large-, mid-, and small-capitalization stocks.

Principal Risks

The Fund is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. An investment in the Fund is not guaranteed. An investor may experience losses. There is no guarantee that the Fund will provide adequate income through retirement. Because bonds and short-term investments are typically less volatile than stocks and because the Fund invests most of its assets in bonds and short-term investments, the Fund's overall level of risk is expected to be low to moderate.

•With approximately 70% of its assets allocated to bonds, the Fund is proportionately subject to the following bond risks: interest rate risk, which is the chance that bond prices will decline because of rising interest rates; income risk, which is the chance that an underlying fund's income will decline because of falling interest rates; credit risk, which is the chance that a bond issuer will fail to pay interest or principal in a timely manner or that negative perceptions of the issuer's ability to make such payments will cause the price of that bond to decline, thus reducing the underlying fund's return; and call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. An underlying fund would then lose any price appreciation above the bond's call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the underlying fund's income. The Fund is also subject to the following risks associated with investments in currency-hedged foreign bonds: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value and/or liquidity of securities issued by foreign governments, government agencies, or companies; and currency hedging risk, which is the chance that the currency hedging transactions entered into by the underlying international bond fund may not perfectly offset the fund's foreign currency exposure.

•With approximately 30% of its assets allocated to stocks, the Fund is proportionately subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund is also subject to the following risks associated

3

with investments in foreign stocks: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value of companies in any one country or region; and currency risk, which is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates. Country/regional risk and currency risk are especially high in emerging markets.

•The Fund is also subject to asset allocation risk, which is the chance that the selection of underlying funds, and the allocation of assets to them, will cause the Fund to underperform other funds with a similar investment objective.

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.

Annual Total Returns

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Fund compare with those of relevant market indexes and a composite bond/stock index, which have investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

Annual Total Returns — Vanguard Target Retirement Income Fund Investor Shares

	2010		2011		2012		2013		2014		2015		2016		2017		2018		2019
40%
20%	9.39		5.25		8.23		5.87		5.54				5.25		8.47				13.16
0%
											-0.17						-1.99
-20%
-40%

During the periods shown in the bar chart, the highest return for a calendar quarter was 5.50% (quarter ended March 31, 2019), and the lowest return for a quarter was –3.20% (quarter ended December 31, 2018).

4

Average Annual Total Returns for Periods Ended December 31, 2019

	1 Year	5 Years	10 Years
Vanguard Target Retirement Income Fund Investor Shares
Return Before Taxes	13.16%	4.80%	5.82%
Return After Taxes on Distributions	12.07	3.75	4.85
Return After Taxes on Distributions and Sale of Fund Shares	7.90	3.35	4.28
Comparative Indexes
(reflect no deduction for fees, expenses, or taxes)
Bloomberg Barclays U.S. Aggregate Bond Index	8.72%	3.05%	3.75%
MSCI US Broad Market Index	31.07	11.26	13.48
Target Income Composite Index	13.41	4.97	5.97

Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

Investment Advisor

The Vanguard Group, Inc. (Vanguard)

Portfolio Managers

William Coleman, CFA, Portfolio Manager at Vanguard. He has co-managed the Fund since 2013.

Walter Nejman, Portfolio Manager at Vanguard. He has co-managed the Fund since 2013.

5

Purchase and Sale of Fund Shares

You may purchase or redeem shares online through our website (vanguard.com), by mail (The Vanguard Group, P.O. Box 1110, Valley Forge, PA 19482-1110), or by telephone (800-662-2739). The minimum investment amount required to open and maintain a Fund account for Investor Shares is $1,000. The minimum investment amount required to add to an existing Fund account is generally $1. Financial intermediaries, institutional clients, and Vanguard-advised clients should contact Vanguard for information on special eligibility rules that may apply to them regarding Investor Shares. If you are investing through an intermediary, please contact that firm directly for more information regarding your eligibility. If you are investing through an employer-sponsored retirement or savings plan, your plan administrator or your benefits office can provide you with detailed information on how you can invest through your plan.

Tax Information

The Fund's distributions may be taxable as ordinary income or capital gain. If you are investing through a tax-advantaged account, such as an IRA or an employer- sponsored retirement or savings plan, special tax rules apply.

Payments to Financial Intermediaries

The Fund and its investment advisor do not pay financial intermediaries for sales of Fund shares.

6

Vanguard Target Retirement 2015 Fund

Investment Objective

The Fund seeks to provide capital appreciation and current income consistent with its current asset allocation.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund.

Shareholder Fees

(Fees paid directly from your investment)

Sales Charge (Load) Imposed on Purchases	None
Purchase Fee	None
Sales Charge (Load) Imposed on Reinvested Dividends	None
Redemption Fee	None
Account Service Fee (for certain fund account balances below $10,000)	$20/year
Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
Management Fees	None
12b-1 Distribution Fee	None
Other Expenses	None
Acquired Fund Fees and Expenses	0.13%
Total Annual Fund Operating Expenses	0.13%

7

Example

The following example is intended to help you compare the cost of investing in the Fund (based on the fees and expenses of the acquired funds) with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you were to invest $10,000 in the Fund's shares. This example assumes that the Fund provides a return of 5% each year and that total annual fund operating expenses of the Fund (and its underlying funds) remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you were to redeem your investment at the end of the given period. 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
$13	$42	$73	$166

Portfolio Turnover

The Fund may pay transaction costs, such as purchase fees, 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 more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 10% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests in other Vanguard mutual funds (underlying funds) according to an asset allocation strategy designed for investors planning to retire and leave the workforce in or within a few years of 2015 (the target year). The Fund is designed for an investor who plans to withdraw the value of an account in the Fund over a period of many years after the target year. The Fund's asset allocation will become more conservative over time, meaning that the percentage of assets allocated to stocks will decrease while the percentage of assets allocated to bonds and other fixed income investments will increase. Within seven years after 2015, the Fund's asset allocation should become similar to that of the Target Retirement Income Fund. As of September 30, 2019, the Fund's asset allocation among the underlying funds was as follows:

• Vanguard Total Bond Market II Index Fund		34.1%
• Vanguard Total Stock Market Index Fund		22.7%
•	Vanguard Total International Stock Index Fund	15.2%
•	Vanguard Total International Bond Index Fund	15.0%
•	Vanguard Short-Term Inflation-Protected Securities Index Fund	13.0%

8

At any given time, the Fund's asset allocation may be affected by a variety of factors, such as whether the underlying funds are accepting additional investments.

The Fund's indirect bond holdings are a diversified mix of short-, intermediate-, and long-term U.S. government, U.S. agency, and investment-grade U.S. corporate bonds; inflation-protected public obligations issued by the U.S. Treasury; mortgage-backed and asset-backed securities; and government, agency, corporate, and securitized investment-grade foreign bonds issued in currencies other than the U.S. dollar (but hedged by Vanguard to minimize foreign currency exposure).

The Fund's indirect stock holdings are a diversified mix of U.S. and foreign large-, mid-, and small-capitalization stocks.

Principal Risks

The Fund is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. An investment in the Fund is not guaranteed. An investor may experience losses, including losses near, at, or after the target year. There is no guarantee that the Fund will provide adequate income at or after the target year. Because fixed income securities such as bonds are typically less volatile than stocks and because the Fund currently invests a significant portion of its assets in fixed income securities, the Fund's overall level of risk is expected to be lower than that of funds investing entirely in stocks.

•With approximately 62% of its assets allocated to bonds, the Fund is proportionately subject to the following bond risks: interest rate risk, which is the chance that bond prices will decline because of rising interest rates; income risk, which is the chance that an underlying fund's income will decline because of falling interest rates; credit risk, which is the chance that a bond issuer will fail to pay interest or principal in a timely manner or that negative perceptions of the issuer's ability to make such payments will cause the price of that bond to decline, thus reducing the underlying fund's return; and call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. An underlying fund would then lose any price appreciation above the bond's call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the underlying fund's income. The Fund is also subject to the following risks associated with investments in currency-hedged foreign bonds: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value and/or liquidity of securities issued by foreign governments, government agencies, or companies; and currency hedging risk, which is the chance that the currency hedging transactions entered into by the underlying international bond fund may not perfectly offset the fund's foreign currency exposure.

9

•With approximately 38% of its assets allocated to stocks, the Fund is proportionately subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund is also subject to the following risks associated with investments in foreign stocks: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value of companies in any one country or region; and currency risk, which is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates. Country/regional risk and currency risk are especially high in emerging markets.

•The Fund is also subject to asset allocation risk, which is the chance that the selection of underlying funds, and the allocation of assets to them, will cause the Fund to underperform other funds with a similar investment objective.

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.

Annual Total Returns

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Fund compare with those of relevant market indexes and a composite bond/stock index, which have investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

Annual Total Returns — Vanguard Target Retirement 2015 Fund Investor Shares

	2010		2011		2012		2013		2014		2015		2016		2017		2018		2019
40%							13.00												14.81
20%	12.47			1.71	11.37				6.56				6.16		11.50
0%
											-0.46						-2.97
-20%
-40%

During the periods shown in the bar chart, the highest return for a calendar quarter was 8.57% (quarter ended September 30, 2010), and the lowest return for a quarter was –8.24% (quarter ended September 30, 2011).

10

Average Annual Total Returns for Periods Ended December 31, 2019

	1 Year	5 Years	10 Years
Vanguard Target Retirement 2015 Fund Investor Shares
Return Before Taxes	14.81%	5.59%	7.25%
Return After Taxes on Distributions	13.22	3.98	6.05
Return After Taxes on Distributions and Sale of Fund Shares	9.34	3.97	5.52
Comparative Indexes
(reflect no deduction for fees, expenses, or taxes)
Bloomberg Barclays U.S. Aggregate Bond Index	8.72%	3.05%	3.75%
MSCI US Broad Market Index	31.07	11.26	13.48
Target 2015 Composite Index	15.08	5.78	7.39

Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

Investment Advisor

The Vanguard Group, Inc. (Vanguard)

Portfolio Managers

William Coleman, CFA, Portfolio Manager at Vanguard. He has co-managed the Fund since 2013.

Walter Nejman, Portfolio Manager at Vanguard. He has co-managed the Fund since 2013.

11

Purchase and Sale of Fund Shares

You may purchase or redeem shares online through our website (vanguard.com), by mail (The Vanguard Group, P.O. Box 1110, Valley Forge, PA 19482-1110), or by telephone (800-662-2739). The minimum investment amount required to open and maintain a Fund account for Investor Shares is $1,000. The minimum investment amount required to add to an existing Fund account is generally $1. Financial intermediaries, institutional clients, and Vanguard-advised clients should contact Vanguard for information on special eligibility rules that may apply to them regarding Investor Shares. If you are investing through an intermediary, please contact that firm directly for more information regarding your eligibility. If you are investing through an employer-sponsored retirement or savings plan, your plan administrator or your benefits office can provide you with detailed information on how you can invest through your plan.

Tax Information

The Fund's distributions may be taxable as ordinary income or capital gain. If you are investing through a tax-advantaged account, such as an IRA or an employer- sponsored retirement or savings plan, special tax rules apply.

Payments to Financial Intermediaries

The Fund and its investment advisor do not pay financial intermediaries for sales of Fund shares.

12

Vanguard Target Retirement 2020 Fund

Investment Objective

The Fund seeks to provide capital appreciation and current income consistent with its current asset allocation.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund.

Shareholder Fees

(Fees paid directly from your investment)

Sales Charge (Load) Imposed on Purchases	None
Purchase Fee	None
Sales Charge (Load) Imposed on Reinvested Dividends	None
Redemption Fee	None
Account Service Fee (for certain fund account balances below $10,000)	$20/year
Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
Management Fees	None
12b-1 Distribution Fee	None
Other Expenses	None
Acquired Fund Fees and Expenses	0.13%
Total Annual Fund Operating Expenses	0.13%

13

Example

The following example is intended to help you compare the cost of investing in the Fund (based on the fees and expenses of the acquired funds) with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you were to invest $10,000 in the Fund's shares. This example assumes that the Fund provides a return of 5% each year and that total annual fund operating expenses of the Fund (and its underlying funds) remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you were to redeem your investment at the end of the given period. 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
$13	$42	$73	$166

Portfolio Turnover

The Fund may pay transaction costs, such as purchase fees, 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 more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 13% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests in other Vanguard mutual funds (underlying funds) according to an asset allocation strategy designed for investors planning to retire and leave the workforce in or within a few years of 2020 (the target year). The Fund is designed for an investor who plans to withdraw the value of an account in the Fund over a period of many years after the target year. The Fund's asset allocation will become more conservative over time, meaning that the percentage of assets allocated to stocks will decrease while the percentage of assets allocated to bonds and other fixed income investments will increase. Within seven years after 2020, the Fund's asset allocation should become similar to that of the Target Retirement Income Fund. As of September 30, 2019, the Fund's asset allocation among the underlying funds was as follows:

• Vanguard Total Stock Market Index Fund		30.9%
• Vanguard Total Bond Market II Index Fund		29.2%
•	Vanguard Total International Stock Index Fund	20.6%
•	Vanguard Total International Bond Index Fund	12.8%
•	Vanguard Short-Term Inflation-Protected Securities Index Fund	6.5%

14

At any given time, the Fund's asset allocation may be affected by a variety of factors, such as whether the underlying funds are accepting additional investments.

The Fund's indirect stock holdings are a diversified mix of U.S. and foreign large-, mid-, and small-capitalization stocks.

The Fund's indirect bond holdings are a diversified mix of short-, intermediate-, and long-term U.S. government, U.S. agency, and investment-grade U.S. corporate bonds; inflation-protected public obligations issued by the U.S. Treasury; mortgage-backed and asset-backed securities; and government, agency, corporate, and securitized investment-grade foreign bonds issued in currencies other than the U.S. dollar (but hedged by Vanguard to minimize foreign currency exposure).

Principal Risks

The Fund is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. An investment in the Fund is not guaranteed. An investor may experience losses, including losses near, at, or after the target year. There is no guarantee that the Fund will provide adequate income at or after the target year. Because stocks are typically more volatile than bonds and because the Fund currently invests most of its assets in stocks, the Fund's overall level of risk should be higher than that of funds that invest the majority of their assets in bonds; however, the level of risk is expected to be lower than that of funds investing entirely in stocks.

•With approximately 51% of its assets allocated to stocks, the Fund is proportionately subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund is also subject to the following risks associated with investments in foreign stocks: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value of companies in any one country or region; and currency risk, which is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates. Country/regional risk and currency risk are especially high in emerging markets.

•With approximately 49% of its assets allocated to bonds, the Fund is proportionately subject to the following bond risks: interest rate risk, which is the chance that bond prices will decline because of rising interest rates; income risk, which is the chance that an underlying fund's income will decline because of falling interest rates; credit risk, which is the chance that a bond issuer will fail to pay interest or principal in a timely manner or that negative perceptions of the issuer's ability to make such payments will cause the price of that bond to decline, thus reducing the underlying fund's return; and call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates

15

before their maturity dates. An underlying fund would then lose any price appreciation above the bond's call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the underlying fund's income. The Fund is also subject to the following risks associated with investments in currency-hedged foreign bonds: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value and/or liquidity of securities issued by foreign governments, government agencies, or companies; and currency hedging risk, which is the chance that the currency hedging transactions entered into by the underlying international bond fund may not perfectly offset the fund's foreign currency exposure.

•The Fund is also subject to asset allocation risk, which is the chance that the selection of underlying funds, and the allocation of assets to them, will cause the Fund to underperform other funds with a similar investment objective.

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.

Annual Total Returns

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Fund compare with those of relevant market indexes and a composite stock/bond index, which have investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

Annual Total Returns — Vanguard Target Retirement 2020 Fund Investor Shares

	2010		2011		2012		2013		2014		2015		2016		2017		2018		2019
40%							15.85								14.08				17.63
20%	13.12				12.35
									7.11				6.95
0%			0.60
-20%											-0.68						-4.24
-40%

During the periods shown in the bar chart, the highest return for a calendar quarter was 9.41% (quarter ended September 30, 2010), and the lowest return for a quarter was –9.94% (quarter ended September 30, 2011).

16

Average Annual Total Returns for Periods Ended December 31, 2019

	1 Year	5 Years	10 Years
Vanguard Target Retirement 2020 Fund Investor Shares
Return Before Taxes	17.63%	6.42%	8.03%
Return After Taxes on Distributions	16.41	5.32	7.16
Return After Taxes on Distributions and Sale of Fund Shares	10.85	4.70	6.25
Comparative Indexes
(reflect no deduction for fees, expenses, or taxes)
MSCI US Broad Market Index	31.07%	11.26%	13.48%
Bloomberg Barclays U.S. Aggregate Bond Index	8.72	3.05	3.75
Target 2020 Composite Index	17.87	6.62	8.26

Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

Investment Advisor

The Vanguard Group, Inc. (Vanguard)

Portfolio Managers

William Coleman, CFA, Portfolio Manager at Vanguard. He has co-managed the Fund since 2013.

Walter Nejman, Portfolio Manager at Vanguard. He has co-managed the Fund since 2013.

17

Purchase and Sale of Fund Shares

You may purchase or redeem shares online through our website (vanguard.com), by mail (The Vanguard Group, P.O. Box 1110, Valley Forge, PA 19482-1110), or by telephone (800-662-2739). The minimum investment amount required to open and maintain a Fund account for Investor Shares is $1,000. The minimum investment amount required to add to an existing Fund account is generally $1. Financial intermediaries, institutional clients, and Vanguard-advised clients should contact Vanguard for information on special eligibility rules that may apply to them regarding Investor Shares. If you are investing through an intermediary, please contact that firm directly for more information regarding your eligibility. If you are investing through an employer-sponsored retirement or savings plan, your plan administrator or your benefits office can provide you with detailed information on how you can invest through your plan.

Tax Information

The Fund's distributions may be taxable as ordinary income or capital gain. If you are investing through a tax-advantaged account, such as an IRA or an employer- sponsored retirement or savings plan, special tax rules apply.

Payments to Financial Intermediaries

The Fund and its investment advisor do not pay financial intermediaries for sales of Fund shares.

18

Vanguard Target Retirement 2025 Fund

Investment Objective

The Fund seeks to provide capital appreciation and current income consistent with its current asset allocation.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund.

Shareholder Fees

(Fees paid directly from your investment)

Sales Charge (Load) Imposed on Purchases	None
Purchase Fee	None
Sales Charge (Load) Imposed on Reinvested Dividends	None
Redemption Fee	None
Account Service Fee (for certain fund account balances below $10,000)	$20/year
Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
Management Fees	None
12b-1 Distribution Fee	None
Other Expenses	None
Acquired Fund Fees and Expenses	0.13%
Total Annual Fund Operating Expenses	0.13%

19

Example

The following example is intended to help you compare the cost of investing in the Fund (based on the fees and expenses of the acquired funds) with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you were to invest $10,000 in the Fund's shares. This example assumes that the Fund provides a return of 5% each year and that total annual fund operating expenses of the Fund (and its underlying funds) remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you were to redeem your investment at the end of the given period. 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
$13	$42	$73	$166

Portfolio Turnover

The Fund may pay transaction costs, such as purchase fees, 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 more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 11% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests in other Vanguard mutual funds (underlying funds) according to an asset allocation strategy designed for investors planning to retire and leave the workforce in or within a few years of 2025 (the target year). The Fund is designed for an investor who plans to withdraw the value of an account in the Fund over a period of many years after the target year. The Fund's asset allocation will become more conservative over time, meaning that the percentage of assets allocated to stocks will decrease while the percentage of assets allocated to bonds and other fixed income investments will increase. Within seven years after 2025, the Fund's asset allocation should become similar to that of the Target Retirement Income Fund. As of September 30, 2019, the Fund's asset allocation among the underlying funds was as follows:

• Vanguard Total Stock Market Index Fund		36.7%
•	Vanguard Total Bond Market II Index Fund	27.3%
•	Vanguard Total International Stock Index Fund	24.4%
•	Vanguard Total International Bond Index Fund	11.6%

20

At any given time, the Fund's asset allocation may be affected by a variety of factors, such as whether the underlying funds are accepting additional investments.

The Fund's indirect stock holdings are a diversified mix of U.S. and foreign large-, mid-, and small-capitalization stocks.

The Fund's indirect bond holdings are a diversified mix of short-, intermediate-, and long-term U.S. government, U.S. agency, and investment-grade U.S. corporate bonds; mortgage-backed and asset-backed securities; and government, agency, corporate, and securitized investment-grade foreign bonds issued in currencies other than the U.S. dollar (but hedged by Vanguard to minimize foreign currency exposure).

Principal Risks

The Fund is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. An investment in the Fund is not guaranteed. An investor may experience losses, including losses near, at, or after the target year. There is no guarantee that the Fund will provide adequate income at or after the target year. Because stocks are typically more volatile than bonds and because the Fund currently invests most of its assets in stocks, the Fund's overall level of risk should be higher than that of funds that invest the majority of their assets in bonds; however, the level of risk is expected to be lower than that of funds investing entirely in stocks.

•With approximately 61% of its assets allocated to stocks, the Fund is proportionately subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund is also subject to the following risks associated with investments in foreign stocks: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value of companies in any one country or region; and currency risk, which is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates. Country/regional risk and currency risk are especially high in emerging markets.

•With approximately 39% of its assets allocated to bonds, the Fund is proportionately subject to the following bond risks: interest rate risk, which is the chance that bond prices will decline because of rising interest rates; income risk, which is the chance that an underlying fund's income will decline because of falling interest rates; credit risk, which is the chance that a bond issuer will fail to pay interest or principal in a timely manner or that negative perceptions of the issuer's ability to make such payments will cause the price of that bond to decline, thus reducing the underlying fund's return; and call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. An underlying fund would then lose any price appreciation

21

above the bond's call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the underlying fund's income. The Fund is also subject to the following risks associated with investments in currency-hedged foreign bonds: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value and/or liquidity of securities issued by foreign governments, government agencies, or companies; and currency hedging risk, which is the chance that the currency hedging transactions entered into by the underlying international bond fund may not perfectly offset the fund's foreign currency exposure.

•The Fund is also subject to asset allocation risk, which is the chance that the selection of underlying funds, and the allocation of assets to them, will cause the Fund to underperform other funds with a similar investment objective.

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.

Annual Total Returns

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Fund compare with those of relevant market indexes and a composite stock/bond index, which have investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

Annual Total Returns — Vanguard Target Retirement 2025 Fund Investor Shares

	2010			2011		2012		2013		2014		2015		2016		2017		2018		2019
40%		13.84				13.29		18.14								15.94				19.63
20%
										7.17				7.48
0%
-20%				-0.37								-0.85						-5.15
-40%

During the periods shown in the bar chart, the highest return for a calendar quarter was 10.12% (quarter ended September 30, 2010), and the lowest return for a quarter was –11.49% (quarter ended September 30, 2011).

22

Average Annual Total Returns for Periods Ended December 31, 2019

	1 Year	5 Years	10 Years
Vanguard Target Retirement 2025 Fund Investor Shares
Return Before Taxes	19.63%	6.99%	8.59%
Return After Taxes on Distributions	18.66	6.01	7.80
Return After Taxes on Distributions and Sale of Fund Shares	11.88	5.18	6.75
Comparative Indexes
(reflect no deduction for fees, expenses, or taxes)
MSCI US Broad Market Index	31.07%	11.26%	13.48%
Bloomberg Barclays U.S. Aggregate Bond Index	8.72	3.05	3.75
Target 2025 Composite Index	19.92	7.20	8.83

Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

Investment Advisor

The Vanguard Group, Inc. (Vanguard)

Portfolio Managers

William Coleman, CFA, Portfolio Manager at Vanguard. He has co-managed the Fund since 2013.

Walter Nejman, Portfolio Manager at Vanguard. He has co-managed the Fund since 2013.

23

Purchase and Sale of Fund Shares

You may purchase or redeem shares online through our website (vanguard.com), by mail (The Vanguard Group, P.O. Box 1110, Valley Forge, PA 19482-1110), or by telephone (800-662-2739). The minimum investment amount required to open and maintain a Fund account for Investor Shares is $1,000. The minimum investment amount required to add to an existing Fund account is generally $1. Financial intermediaries, institutional clients, and Vanguard-advised clients should contact Vanguard for information on special eligibility rules that may apply to them regarding Investor Shares. If you are investing through an intermediary, please contact that firm directly for more information regarding your eligibility. If you are investing through an employer-sponsored retirement or savings plan, your plan administrator or your benefits office can provide you with detailed information on how you can invest through your plan.

Tax Information

The Fund's distributions may be taxable as ordinary income or capital gain. If you are investing through a tax-advantaged account, such as an IRA or an employer- sponsored retirement or savings plan, special tax rules apply.

Payments to Financial Intermediaries

The Fund and its investment advisor do not pay financial intermediaries for sales of Fund shares.

24

Vanguard Target Retirement 2030 Fund

Investment Objective

The Fund seeks to provide capital appreciation and current income consistent with its current asset allocation.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund.

Shareholder Fees

(Fees paid directly from your investment)

Sales Charge (Load) Imposed on Purchases	None
Purchase Fee	None
Sales Charge (Load) Imposed on Reinvested Dividends	None
Redemption Fee	None
Account Service Fee (for certain fund account balances below $10,000)	$20/year
Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
Management Fees	None
12b-1 Distribution Fee	None
Other Expenses	None
Acquired Fund Fees and Expenses	0.14%
Total Annual Fund Operating Expenses	0.14%

25

Example

The following example is intended to help you compare the cost of investing in the Fund (based on the fees and expenses of the acquired funds) with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you were to invest $10,000 in the Fund's shares. This example assumes that the Fund provides a return of 5% each year and that total annual fund operating expenses of the Fund (and its underlying funds) remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you were to redeem your investment at the end of the given period. 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
$14	$45	$79	$179

Portfolio Turnover

The Fund may pay transaction costs, such as purchase fees, 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 more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 8% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests in other Vanguard mutual funds (underlying funds) according to an asset allocation strategy designed for investors planning to retire and leave the workforce in or within a few years of 2030 (the target year). The Fund is designed for an investor who plans to withdraw the value of an account in the Fund over a period of many years after the target year. The Fund's asset allocation will become more conservative over time, meaning that the percentage of assets allocated to stocks will decrease while the percentage of assets allocated to bonds and other fixed income investments will increase. Within seven years after 2030, the Fund's asset allocation should become similar to that of the Target Retirement Income Fund. As of September 30, 2019, the Fund's asset allocation among the underlying funds was as follows:

•	Vanguard Total Stock Market Index Fund	41.1%
•	Vanguard Total International Stock Index Fund	27.4%
• Vanguard Total Bond Market II Index Fund		22.1%
•	Vanguard Total International Bond Index Fund	9.4%

26

At any given time, the Fund's asset allocation may be affected by a variety of factors, such as whether the underlying funds are accepting additional investments.

The Fund's indirect stock holdings are a diversified mix of U.S. and foreign large-, mid-, and small-capitalization stocks.

The Fund's indirect bond holdings are a diversified mix of short-, intermediate-, and long-term U.S. government, U.S. agency, and investment-grade U.S. corporate bonds; mortgage-backed and asset-backed securities; and government, agency, corporate, and securitized investment-grade foreign bonds issued in currencies other than the U.S. dollar (but hedged by Vanguard to minimize foreign currency exposure).

Principal Risks

The Fund is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. An investment in the Fund is not guaranteed. An investor may experience losses, including losses near, at, or after the target year. There is no guarantee that the Fund will provide adequate income at or after the target year. Because stocks are typically more volatile than bonds and because the Fund currently invests most of its assets in stocks, the Fund's overall level of risk should be higher than that of funds that invest the majority of their assets in bonds; however, the level of risk is expected to be lower than that of funds investing entirely in stocks.

•With approximately 69% of its assets allocated to stocks, the Fund is proportionately subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund is also subject to the following risks associated with investments in foreign stocks: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value of companies in any one country or region; and currency risk, which is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates. Country/regional risk and currency risk are especially high in emerging markets.

•With approximately 31% of its assets allocated to bonds, the Fund is proportionately subject to the following bond risks: interest rate risk, which is the chance that bond prices will decline because of rising interest rates; income risk, which is the chance that an underlying fund's income will decline because of falling interest rates; credit risk, which is the chance that a bond issuer will fail to pay interest or principal in a timely manner or that negative perceptions of the issuer's ability to make such payments will cause the price of that bond to decline, thus reducing the underlying fund's return; and call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. An underlying fund would then lose any price appreciation

27

above the bond's call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the underlying fund's income. The Fund is also subject to the following risks associated with investments in currency-hedged foreign bonds: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value and/or liquidity of securities issued by foreign governments, government agencies, or companies; and currency hedging risk, which is the chance that the currency hedging transactions entered into by the underlying international bond fund may not perfectly offset the fund's foreign currency exposure.

•The Fund is also subject to asset allocation risk, which is the chance that the selection of underlying funds, and the allocation of assets to them, will cause the Fund to underperform other funds with a similar investment objective.

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.

Annual Total Returns

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Fund compare with those of relevant market indexes and a composite stock/bond index, which have investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

Annual Total Returns — Vanguard Target Retirement 2030 Fund Investor Shares

	2010			2011		2012		2013		2014		2015		2016		2017		2018		2019
40%		14.43				14.24		20.49								17.52				21.07
20%														7.85
0%										7.17
-20%				-1.27								-1.03						-5.86
-40%

During the periods shown in the bar chart, the highest return for a calendar quarter was 10.95% (quarter ended September 30, 2010), and the lowest return for a quarter was –13.04% (quarter ended September 30, 2011).