VTEB Vanguard Tax Exempt Bond ETF

Vanguard Municipal Money Market Fund Summary Prospectus

February 27, 2020

Investor Shares

Vanguard Municipal Money Market Fund Investor Shares (VMSXX)

The Fund's statutory Prospectus and Statement of Additional Information dated February 27, 2020, as may be amended or supplemented, are incorporated into and made part of this Summary Prospectus by reference.

Before you invest, you may want to review the Fund's Prospectus, which contains more information about the Fund and its risks. You can find the Fund's Prospectus and other information about the Fund online at www.vanguard.com/prospectus. You can also obtain this information at no cost by calling 800-662-7447 or by sending an email request to online@vanguard.com.

See the inside front cover for important information about access to your fund's annual and semiannual shareholder reports.

The Securities and Exchange Commission (SEC) has not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense.

Important information about access to shareholder reports

Beginning on January 1, 2021, as permitted by regulations adopted by the SEC, paper copies of your fund's annual and semiannual shareholder reports will no longer be sent to you by mail, unless you specifically request them. Instead, you will be notified by mail each time a report is posted on the website and will be provided with a link to access the report.

If you have already elected to receive shareholder reports electronically, you will not be affected by this change and do not need to take any action. You may elect to receive shareholder reports and other communications from the fund electronically by contacting your financial intermediary (such as a broker-dealer or bank) or, if you invest directly with the fund, by calling Vanguard at one of the phone numbers on the back cover of this prospectus or by logging on to vanguard.com.

You may elect to receive paper copies of all future shareholder reports free of charge. If you invest through a financial intermediary, you can contact the intermediary to request that you continue to receive paper copies. If you invest directly with the fund, you can call Vanguard at one of the phone numbers on the back cover of this prospectus or log on to vanguard.com. Your election to receive paper copies will apply to all the funds you hold through an intermediary or directly with Vanguard.

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such payments will cause the price of that security to decline. Credit risk should be very low for the Fund because it invests primarily in securities that are considered to be of high quality.

•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.

•Tax risk, which is the chance that all or a portion of the tax-exempt income from municipal bonds held by the Fund will be declared taxable, possibly with retroactive effect, because of unfavorable changes in tax laws, adverse interpretations by the Internal Revenue Service or state or local tax authorities, or noncompliant conduct of a bond issuer.

•Derivatives risk. The Fund may invest in structured products such as tender option bonds and long-term municipal securities combined with a demand feature (e.g., variable rate demand notes or VRDNs), which may involve risks different from, and possibly greater than, those of investments directly in the underlying securities or assets.

You could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The Fund may impose a fee upon sale of your shares or may temporarily suspend your ability to sell shares if the Fund's liquidity falls below required minimums because of market conditions or other factors. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund's sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time.

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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 a comparative benchmark, which has investment characteristics similar to those of the Fund. Returns for the Municipal Money Market Funds Average are derived from data provided by Lipper, a Thomson Reuters Company. Keep in mind that the Fund's past performance 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.

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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). When your trade is processed depends on the day and time Vanguard receives your request in good order and the manner in which it is submitted. Generally, trades placed after the close of business are processed during the next business day. The minimum investment amount required to open and maintain a Fund account for Investor Shares is $3,000. The minimum investment amount required to add to an existing Fund account is generally $1. Financial intermediaries 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. The Fund is only eligible for purchase within accounts beneficially owned by natural persons.

Tax Information

The Fund's distributions may be taxable as ordinary income or capital gain. A majority of the income dividends that you receive from the Fund are expected to be exempt from federal income taxes. However, a portion of the Fund's distributions may be subject to federal, state, or local income taxes or the federal alternative minimum tax.

Payments to Financial Intermediaries

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

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Vanguard Municipal Money Market Fund Investor Shares—Fund Number 45

CFA® is a registered trademark owned by CFA Institute.

To request additional information about the Fund, please visit vanguard.com or contact us at 800-662-7447.

© 2020 The Vanguard Group, Inc. All rights reserved. Vanguard Marketing Corporation, Distributor.

SP 45 022020