Form 497K VANGUARD FIXED INCOME

Investment Objective

The Fund seeks to provide a high and sustainable level of current income.

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.

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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 invested $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 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:

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 35% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests in a variety of high-quality and, to a lesser extent, medium-quality fixed income securities, at least 80% of which will be intermediate- and long-term investment-grade securities. High-quality fixed income securities are those rated the equivalent of A3 or better by Moody‘s Investors Service, Inc., or another independent rating agency or, if unrated, are determined to be of comparable quality by the Fund’s advisor; medium-quality fixed income securities are those rated the equivalent of Baa1, Baa2, or Baa3 by Moody‘s or another independent rating agency or, if unrated, are determined to be of comparable quality by the Fund’s advisor. (Investment-grade fixed income securities are those rated the equivalent of Baa3 and above by Moody‘s or another independent rating agency or, if unrated, are determined to be of comparable quality by the Fund’s advisor.) The Fund’s dollar-weighted average maturity is expected to fall within a range that is five years shorter than or five years longer than that of its benchmark index, which had a dollar-weighted average maturity of 23.2 years as of January 31, 2016. The Fund uses multiple investment advisors.

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Principal Risks

An investment in the Fund could lose money over short or even long periods. 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:

• Interest rate risk, which is the chance that bond prices will decline because of rising interest rates. Interest rate risk should be high for the Fund because it invests primarily in long-term bonds, whose prices are more sensitive to interest rate changes than are the prices of shorter-term bonds.

• Liquidity risk, which is the chance that the Fund may not be able to sell a security in a timely manner at a desired price. Liquidity risk is generally high for long-term corporate bonds.

• 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. The 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 Fund’s income. Such redemptions and subsequent reinvestments would also increase the Fund’s portfolio turnover rate. Call risk should be moderate for the Fund. To minimize the impact of call risk, the advisors generally seek to purchase bonds that have reasonable protection from being called.

• Extension risk, which is the chance that during periods of rising interest rates, certain debt securities will be paid off substantially more slowly than originally anticipated, and the value of those securities may fall. Extension risk is generally high for long-term bond funds.

• 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. Although the Fund invests a limited portion of its assets in low-quality bonds, credit risk should be low for the Fund because it invests primarily in bonds that are considered high-quality and, to a lesser extent, in bonds that are considered medium-quality.

• Income risk, which is the chance that the Fund’s income will decline because of falling interest rates. Income risk should be low for the Fund because it invests primarily in long-term bonds.

• 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.

• Derivatives risk. The Fund may invest in derivatives, which may involve risks different from, and possibly greater than, those of investments directly in the underlying securities or assets.

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.

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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‘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 Long-Term Investment-Grade Fund Investor Shares¹

1 The year-to-date return as of the most recent calendar quarter, which ended on March 31, 2016, was 6.77%.

During the periods shown in the bar chart, the highest return for a calendar quarter was 11.33% (quarter ended September 30, 2009), and the lowest return for a quarter was –8.28% (quarter ended March 31, 2009).

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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 Advisors

Wellington Management Company LLP (Wellington Management)

The Vanguard Group, Inc. (Vanguard)

Portfolio Managers

Lucius T. Hill, III, Senior Managing Director and Fixed Income Portfolio Manager of Wellington Management. He has managed the Fund since 2008 (co-managed a portion since 2014).

Scott I. St. John, CFA, Senior Managing Director and Fixed Income Portfolio Manager of Wellington Management. He has co-managed a portion of the Fund since 2014.

Gregory S. Nassour, CFA, Principal of Vanguard. He has managed a portion of the Fund since 2013.

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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. Institutional, financial intermediary, and Vanguard retail managed clients should contact Vanguard for information on special eligibility rules that may apply to them regarding Admiral Shares.

Tax Information

The Fund’s distributions may be taxable as ordinary income or capital gain. If you are investing through a tax-deferred retirement account, such as an IRA, special tax rules apply.

Payments to Financial Intermediaries

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

Vanguard Long-Term Investment-Grade Fund Investor Shares—Fund Number 28 Vanguard Long-Term Investment-Grade Fund Admiral Shares—Fund Number 568

CFA^® is a registered trademark owned by CFA Institute.

Vanguard Long-Term Investment-Grade Fund is not sponsored, endorsed, issued, sold or promoted by Barclays Capital Inc. or any of its affiliates (“Barclays”). Barclays makes no representation or warranty, express or implied, to the owners or purchasers of Vanguard Long-Term Investment-Grade Fund or any member of the public regarding the advisability of investing in securities generally or in Vanguard Long-Term Investment-Grade Fund particularly or the ability of the Barclays Index to track general bond market performance. Barclays has not passed on the legality or suitability of the Vanguard Long-Term Investment-Grade Fund with respect to any person or entity. Barclays’ only relationship to Vanguard and Vanguard Long-Term Investment-Grade Fund is the licensing of the Barclays Index which is determined, composed and calculated by Barclays without regard to Vanguard or the Vanguard Long-Term Investment-Grade Fund or any owners or purchasers of the Vanguard Long-Term Investment-Grade Fund. Barclays has no obligation to take the needs of Vanguard, Vanguard Long-Term Investment-Grade Fund or the owners of Vanguard Long-Term Investment-Grade Fund into consideration in determining, composing or calculating the Barclays Index. Barclays is not responsible for and has not participated in the determination of the timing of, prices at, or quantities of Vanguard Long-Term Investment-Grade Fund to be issued. Barclays has no obligation or liability in connection with the administration, marketing or trading of the Vanguard Long-Term Investment-Grade Fund.

BARCLAYS SHALL HAVE NO LIABILITY TO THIRD PARTIES FOR THE QUALITY, ACCURACY AND/OR COMPLETENESS OF THE INDEX OR ANY DATA INCLUDED THEREIN OR FOR INTERRUPTIONS IN THE DELIVERY OF THE INDEX. BARCLAYS MAKES NO WARRANTY, EXPRESS OR IMPLIED, AS TO RESULTS TO BE OBTAINED BY OWNERS OF THE VANGUARD LONG-TERM INVESTMENT-GRADE FUND OR ANY OTHER PERSON OR ENTITY FROM THE USE OF THE INDEX OR ANY DATA INCLUDED THEREIN IN CONNECTION WITH THE RIGHTS LICENSED HEREUNDER OR FOR ANY OTHER USE. BARCLAYS RESERVES THE RIGHT TO CHANGE THE METHODS OF CALCULATION OR PUBLICATION, OR TO CEASE THE CALCULATION OR PUBLICATION OF THE BARCLAYS INDICES, AND BARCLAYS SHALL NOT BE LIABLE FOR ANY MISCALCULATION OF OR ANY INCORRECT, DELAYED OR INTERRUPTED PUBLICATION WITH RESPECT TO ANY OF THE BARCLAYS INDICES. BARCLAYS MAKES NO EXPRESS OR IMPLIED WARRANTIES, AND HEREBY EXPRESSLY DISCLAIMS ALL WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE WITH RESPECT TO THE INDEX OR ANY DATA INCLUDED THEREIN. BARCLAYS SHALL NOT BE LIABLE FOR ANY DAMAGES, INCLUDING, WITHOUT LIMITATION, ANY INDIRECT OR CONSEQUENTIAL DAMAGES RESULTING FROM THE USE OF THE INDEX OR ANY DATA INCLUDED THEREIN.

©2016 Barclays. Used with Permission.

Source: Barclays Global Family of Indices. Copyright 2016, Barclays. All rights reserved.

© 2016 The Vanguard Group, Inc. All rights reserved.

Vanguard Marketing Corporation, Distributor.

SP 28 052016