485BPOS
Vanguard Variable Insurance Funds
Total Bond Market Index Portfolio
April 28, 2023
Prospectus

This prospectus contains financial data for the Portfolio through the fiscal year ended December 31, 2022.

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.

Contents

Portfolio Summary
Investment Objective
The Portfolio seeks to track the performance of a broad, market-weighted bond index.
Fees and Expenses
The following table describes the fees and expenses you may pay if you buy, hold, and sell shares of the Portfolio. The expenses shown in the table and in the example that follows do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher.
Annual Portfolio Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
 
Management Fees
0.13%
12b-1 Distribution Fee
None
Other Expenses
0.01%
Total Annual Portfolio Operating Expenses
0.14%
Example
The following example is intended to help you compare the cost of investing in the Portfolio 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 Portfolio's shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio 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
$14
$45
$79
$179
Portfolio Turnover
The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio's performance. During the most recent fiscal year, the Portfolio's turnover rate was 42% of the average value of its portfolio.
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Principal Investment Strategies
Vanguard Variable Insurance Funds Total Bond Market Index Portfolio (the Total Bond Market Index Portfolio) employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Aggregate Float Adjusted Index. This Index measures the performance of a wide spectrum of public, investment-grade, taxable, fixed income securities in the United States—including government, corporate, and international dollar-denominated bonds, as well as mortgage-backed and asset-backed securities—all with maturities of more than 1 year.


The Portfolio invests by sampling the Index, meaning that it holds a broadly diversified collection of securities that, in the aggregate, approximates the full Index in terms of key risk factors and other characteristics. All of the Portfolio's investments will be selected through the sampling process and, under normal circumstances, at least 80% of the Portfolio's assets will be invested in bonds held in the Index. The Portfolio maintains a dollar-weighted average maturity consistent with that of the Index. As of December 31, 2022, the dollar-weighted average maturity of the Index was 8.5 years. The Portfolio also seeks to maintain an average duration consistent with that of the Index. As of December 31, 2022, the average duration of the Index was 6.2 years.
Principal Risks
An investment in the Portfolio could lose money over short or long periods of time. You should expect the Portfolio's share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio's performance, and the level of risk may vary based on market conditions:
• Interest rate risk, which is the chance that bond prices overall will decline because of rising interest rates. Interest rate risk should be moderate for the Portfolio because it invests primarily in short- and intermediate-term bonds, whose prices are less sensitive to interest rate changes than are the prices of long-term bonds.
• Income risk, which is the chance that the Portfolio’s income will decline because of falling interest rates. Income risk is generally high for short-term bond funds and moderate for intermediate-term bond funds, so investors should expect the Portfolio’s monthly income to fluctuate accordingly.
• Prepayment risk, which is the chance that during periods of falling interest rates, homeowners will refinance their mortgages before their maturity dates, resulting in prepayment of mortgage-backed securities held by the Portfolio. The Portfolio would then lose any price appreciation above the mortgage’s principal and would be forced to reinvest the unanticipated proceeds at lower interest
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rates, resulting in a decline in the Portfolio’s income. Such prepayments and subsequent reinvestments would also increase the Portfolio’s turnover rate. Prepayment risk should be moderate for the Portfolio.
• 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. For funds that invest in mortgage-backed securities, extension risk is the chance that during periods of rising interest rates, homeowners will repay their mortgages at slower rates. This will lengthen the duration or average life of mortgage-backed securities held by the Portfolio and delay the Portfolio's ability to reinvest proceeds at higher interest rates. Extension risk should be moderate for the Portfolio.
• 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 Portfolio 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 Portfolio’s income. Such redemptions and subsequent reinvestments would also increase the Portfolio’s turnover rate. Call risk should be low for the Portfolio because it invests only a small portion of its assets in callable bonds.
• 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. Credit risk should be low for the Portfolio because it purchases only bonds that are of investment-grade quality.
• Index sampling risk, which is the chance that the securities selected for the Portfolio, in the aggregate, will not provide investment performance matching that of the Portfolio’s target index. Index sampling risk for the Portfolio is expected to be low.
• Liquidity risk, which is the chance that the Portfolio may not be able to sell a security in a timely manner at a desired price.
An investment in the Portfolio 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 Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of its target index, which has investment characteristics similar to
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those of the Portfolio. The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio's past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555.
Annual Total Returns — Total Bond Market Index Portfolio
During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:
 
Total Return
Quarter
Highest
3.21%
March 31, 2020
Lowest
-5.98%
March 31, 2022
Average Annual Total Returns for Periods Ended December 31, 2022
 
1 Year
5 Years
10 Years
Total Bond Market Index Portfolio
-13.21%
-0.10%
0.92%
Bloomberg U.S. Aggregate Float Adjusted Index
(reflects no deduction for fees, expenses, or taxes)
-13.07%
0.06%
1.08%
Investment Advisor
The Vanguard Group, Inc. (Vanguard)
Portfolio Manager
Joshua C. Barrickman, CFA, Principal of Vanguard and co-head of Vanguard’s Fixed Income Indexing Americas. He has managed the Portfolio since 2013.
Tara Talone, CFA, Portfolio Manager at Vanguard. She has co-managed the Portfolio since September 2022.
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Tax Information
The Portfolio normally distributes its net investment income and net realized capital gains, if any, to its shareholders, which are the insurance company separate accounts that sponsor your variable annuity or variable life insurance contract. The tax consequences to you of your investment in the Portfolio depend on the provisions of the annuity or life insurance contract through which you invest. For more information on taxes, please refer to the prospectus of the annuity or life insurance contract through which Portfolio shares are offered.
Payments to Financial Intermediaries
The Portfolio and its investment advisor do not pay financial intermediaries for sales of Portfolio shares.
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More on the Portfolio
This prospectus describes the principal risks you would face as an investor in this Portfolio. 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 Portfolio investor. 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 Portfolio is the right investment for you. We suggest that you keep this prospectus for future reference.
A Note About Vanguard Variable Insurance Funds
The Total Bond Market Index Portfolio of Vanguard Variable Insurance Funds is a mutual fund used solely as an investment option for annuity or life insurance contracts offered by insurance companies. This means that you cannot purchase shares of the Portfolio directly, but only through a contract offered by an insurance company.
The Total Bond Market Index Portfolio is separate from other Vanguard mutual funds, even when the Portfolio and a fund have the same investment objective and advisor. The Portfolio’s investment performance will differ from the performance of other Vanguard funds because of differences in the securities held and because of administrative and insurance costs associated with the annuity or life insurance program through which you invest.
Plain Talk About Costs of Investing
Costs are an important consideration in choosing a mutual fund. That is
because you, as a contract owner, 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.
The following sections explain the principal investment strategies and policies that the Portfolio uses in pursuit of its investment objective. The board of trustees of Vanguard Variable Insurance Funds (the Board), which oversees the Portfolio's management, may change investment strategies or policies in the
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interest of shareholders without a shareholder vote, unless those strategies or policies are designated as fundamental. The Portfolio may change its policy of investing at least 80% of its assets in bonds that are part of its target index only upon 60 days‘ notice to shareholders.
Market Exposure
The Portfolio invests in public, investment-grade, taxable, fixed income securities in the United States, as well as mortgage-backed and asset-backed securities.
Plain Talk About Types of Bonds
Bonds are issued (sold) by many sources: Corporations issue corporate
bonds; the federal government issues U.S. Treasury bonds; agencies of the
federal government issue agency bonds; financial institutions issue
asset-backed bonds; and mortgage holders issue “mortgage-backed”
pass-through certificates. Each issuer is responsible for paying back the
bond’s initial value as well as for making periodic interest payments. Many
bonds issued by government agencies and entities are neither guaranteed
nor insured by the U.S. government.
The Portfolio is subject to interest rate risk, which is the chance that bond
prices overall will decline because of rising interest rates.
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Plain Talk About Bonds and Interest Rates
As a rule, when interest rates rise, bond prices fall. The opposite is also true:
Bond prices go up when interest rates fall. Why do bond prices and interest
rates move in opposite directions? Let’s assume that you hold a bond
offering a 4% yield. A year later, interest rates are on the rise and bonds of
comparable quality and maturity are offered with a 5% yield. With
higher-yielding bonds available, you would have trouble selling your 4% bond
for the price you paid—you would probably have to lower your asking price.
On the other hand, if interest rates were falling and 3% bonds were being
offered, you should be able to sell your 4% bond for more than you paid.
How mortgage-backed securities are different: In general, declining interest
rates will not lift the prices of mortgage-backed securities—such as those
guaranteed by the Government National Mortgage Association—as much as
the prices of comparable bonds. Why? Because when interest rates fall, the
bond market tends to discount the prices of mortgage-backed securities for
prepayment risk—the possibility that homeowners will refinance their
mortgages at lower rates and cause the bonds to be paid off prior to
maturity. In part to compensate for this prepayment possibility,
mortgage-backed securities tend to offer higher yields than other bonds of
comparable credit quality and maturity. In contrast, when interest rates rise,
prepayments tend to slow down, subjecting mortgage-backed securities to
extension risk—the possibility that homeowners will repay their mortgages
at slower rates. This will lengthen the duration or average life of
mortgage-backed securities held by a fund and delay the fund’s ability to
reinvest proceeds at higher interest rates, making the fund more sensitive to
changes in interest rates.
In general, interest rate fluctuations widen as a bond portfolio’s average maturity lengthens. The Portfolio is expected to have a moderate level of interest rate risk because its holdings have an intermediate-term average maturity.
The Portfolio is subject to income risk, which is the chance that the Portfolio's income will decline because of falling interest rates. A portfolio's income declines when interest rates fall because the portfolio then must invest new cash flow and cash from maturing bonds in lower-yielding bonds.
In general, income risk is higher for short-term bond funds and lower for long-term bond funds. Accordingly, the Portfolio should have a moderate level of income risk.
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Plain Talk About Bond Maturities
A bond is issued with a specific maturity date—the date when the issuer
must pay back the bond’s principal (face value). Bond maturities range from
less than 1 year to more than 30 years. Typically, the longer a bond’s maturity,
the more price risk you, as a bond investor, will face as interest rates
rise—but also the higher the potential yield you could receive. Longer-term
bonds are generally more suitable for investors willing to take a greater risk
of price fluctuations to get higher and more stable interest income.
Shorter-term bond investors should be willing to accept lower yields and
greater income variability in return for less fluctuation in the value of their
investment. The stated maturity of a bond may differ from the effective
maturity of a bond, which takes into consideration that an action such as a
call or refunding may cause bonds to be repaid before their stated
maturity dates.
The Portfolio is subject to 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.
Plain Talk About Credit Quality
A bond’s credit quality rating is an assessment of the issuer’s ability to pay
interest on the bond and, ultimately, to repay the principal. The lower the
credit quality, the greater the perceived chance that the bond issuer will
default, or fail to meet its payment obligations. All things being equal, the
lower a bond’s credit quality, the higher its yield should be to compensate
investors for assuming additional risk.
Credit risk should be low for the Portfolio because it invests mainly in fixed income securities with high credit quality ratings.
To a limited extent, the Portfolio is subject to event risk, which is the chance that corporate fixed income securities held by the Portfolio may suffer a substantial decline in credit quality and market value because of a restructuring of the companies that issued the securities or because of other factors negatively affecting the issuers.
The Portfolio is subject to liquidity risk, which is the chance that the Portfolio may not be able to sell a security in a timely manner at a desired price.
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Corporate bonds are traded among dealers and brokers that connect buyers with sellers. Liquidity in the corporate bond market may be challenged depending on overall economic conditions and credit tightening. There may be little trading in the secondary market for particular bonds and other debt securities, which may make them more difficult to value or sell.
Market disruptions can adversely affect local and global markets as well as normal market conditions and operations. Any such disruptions could have an adverse impact on the value of the Portfolio's investments and Portfolio performance.
Security Selection
Because it would be very expensive and inefficient to buy and sell all securities held in its target index, the Total Bond Market Index Portfolio uses index “sampling” techniques to select securities. Using computer programs, the Portfolio’s advisor generally selects a representative sample of securities that approximates the full target index in terms of key risk factors and other characteristics. These factors include duration, cash flow, quality, and callability of the underlying bonds. In addition, the Portfolio keeps industry sector and subsector exposure within tight boundaries relative to its target index. Because the Portfolio does not hold all of the securities included in its target index, some of the securities (and issuers) that are held will likely be overweighted (or underweighted) compared with the target index. The maximum overweight (or underweight) is constrained at the issuer level with the goal of producing well-diversified credit exposure in the Portfolio.
The Portfolio is subject to index sampling risk, which is the chance that the securities selected for the Portfolio, in the aggregate, will not provide investment performance matching that of the Portfolio's target index. Index sampling risk for the Portfolio is expected to be low.
The Bloomberg U.S. Aggregate Float Adjusted Index measures the performance of a wide spectrum of public, investment-grade, taxable, fixed income securities in the United States—including government, corporate, and international
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dollar-denominated bonds, as well as mortgage-backed and asset-backed securities—all with maturities of more than 1 year. As of December 31, 2022, the Portfolio was composed of the following types of bonds:
Type of Bond
Portion of Portfolio’s
Net Assets
Treasury/Agency
45.6%
Government Mortgage-Backed
20.4
Industrial
15.6
Finance
9.2
Foreign
3.5
Asset-Backed/Commercial Mortgage-Backed
2.6
Utilities
2.3
Other
0.8
Up to 20% of the Portfolio’s assets may be used to purchase nonpublic, investment-grade securities, generally referred to as 144A securities, as well as smaller public issues or medium-term notes not included in the Index because of the small size of the issue. The Portfolio’s advisor expects that the vast majority of these securities will have characteristics and risks similar to those in the target index. Subject to the same 20% limit, the Portfolio may also purchase other investments that are outside of its target index or may hold bonds that, when acquired, were included in the index but subsequently were removed. The Portfolio may invest a portion of its assets in callable bonds.
The Portfolio is subject to prepayment risk, which is the chance that during periods of falling interest rates, homeowners will refinance their mortgages before their maturity dates, resulting in prepayment of mortgage-backed securities held by the Portfolio. The Portfolio would then lose any price appreciation above the mortgage’s principal and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Portfolio’s income. Such prepayments and subsequent reinvestments would also increase the Portfolio’s turnover rate. Prepayment risk should be moderate for the Portfolio.
The Portfolio is subject to 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. For funds that invest in mortgage-backed securities, extension risk is the chance that during periods of rising interest rates, homeowners will repay their mortgages at slower rates. This will lengthen the duration or average life of mortgage-backed securities held by the Portfolio and delay the Portfolio's ability to reinvest proceeds at higher interest rates. Extension risk should be moderate for the Portfolio.
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The Portfolio is subject to 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 Portfolio 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 Portfolio’s income. Such redemptions and subsequent reinvestments would also increase the Portfolio’s turnover rate. Call risk should be low for the Portfolio because it invests only a small portion of its assets in callable bonds.
Plain Talk About Callable Bonds
Although bonds are issued with clearly defined maturities, in some cases the
bond issuer has a right to call in (redeem) the bond earlier than its maturity
date. When a bond is called, the bondholder may have to replace it with
another bond with a lower yield than the original bond. One way for bond
investors to protect themselves against call risk is to purchase a bond early
in its lifetime, long before its call date. Another way is to buy bonds with
lower coupon rates or interest rates, which make them less likely to
be called.
The Portfolio may invest a portion of its assets in mortgage-backed securities, which represent interests in underlying pools of mortgages. Unlike ordinary bonds, which generally pay a fixed rate of interest at regular intervals and then repay principal upon maturity, mortgage-backed securities pass through both interest and principal from underlying mortgages as part of their regular payments. Because the mortgages underlying the securities can be prepaid at any time by homeowners or corporate borrowers, mortgage-backed securities are subject to prepayment risk. These types of securities are issued by a number of government agencies, including the GNMA, the FHLMC, and the FNMA. Mortgage-backed securities issued by the GNMA are guaranteed by the full faith and credit of the U.S. government as to the timely payment of principal and interest; those issued by other government agencies or private corporations are not.
The Portfolio may also invest in conventional mortgage-backed securities—which are packaged by private corporations and are not guaranteed by the U.S. government—and enter into mortgage-dollar-roll transactions. In a mortgage-dollar-roll transaction, the Portfolio sells mortgage-backed securities to a dealer and simultaneously agrees to purchase similar securities in the future at a predetermined price. These transactions simulate an investment in mortgage-backed securities and have the potential to enhance the Portfolio’s returns and reduce its administrative burdens, compared with holding
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mortgage-backed securities directly. These transactions may increase the Portfolio’s turnover rate. Mortgage dollar rolls will be used only to the extent that they are consistent with the Portfolio’s investment objective and risk profile.
Plain Talk About U.S. Government-Sponsored Enterprises
A variety of U.S. government-sponsored enterprises (GSEs), such as the
Federal Home Loan Mortgage Corporation (FHLMC), the Federal National
Mortgage Association (FNMA), and the Federal Home Loan Banks (FHLBs),
issue debt and mortgage-backed securities. Although GSEs may be chartered
or sponsored by acts of Congress, they are not funded by congressional
appropriations. In September of 2008, the U.S. Treasury placed FNMA and
FHLMC under conservatorship and appointed the Federal Housing Finance
Agency (FHFA) to manage their daily operations. In addition, the U.S. Treasury
entered into purchase agreements with FNMA and FHLMC to provide them
with capital in exchange for senior preferred stock. Generally, a GSE’s
securities are neither issued nor guaranteed by the U.S. Treasury and are not
backed by the full faith and credit of the U.S. government. In most cases,
these securities are supported only by the credit of the GSE, standing alone. In
some cases, a GSE’s securities may be supported by the ability of the GSE to
borrow from the U.S. Treasury or may be supported by the U.S. government in
some other way. Securities issued by the Government National Mortgage
Association (GNMA), however, are backed by the full faith and credit of the
U.S. government.
Other Investment Policies and Risks
The Portfolio reserves the right to substitute a different index for the index it currently tracks if the current index is discontinued, if the Portfolio's agreement with the sponsor of its target index is terminated, or for any other reason determined in good faith by the Board. In any such instance, the substitute index would represent the same market segment as the current index.
The Portfolio may invest in international U.S. dollar-denominated bonds issued by foreign governments, government agencies, and companies. To the extent that the Portfolio owns foreign bonds, it is subject to country 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. Because the bond’s value is designated in dollars rather than in the currency of the issuer’s country, the Portfolio is not exposed to currency risk; rather, the issuer assumes the risk, usually to attract U.S. investors.
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The Portfolio may also invest in relatively conservative classes of collateralized mortgage obligations (CMOs), which offer a high degree of cash-flow predictability and a low level of vulnerability to mortgage prepayment risk. To reduce credit risk, these less-risky classes of CMOs are purchased only if they are issued by agencies of the U.S. government or issued by private companies that carry high-quality investment-grade ratings.
The Portfolio may invest in derivatives. In general, investments in derivatives may involve risks different from, and possibly greater than, those of investments directly in the underlying securities or assets.
The Portfolio may also invest 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 market index, or a reference rate.
The Portfolio may invest in fixed income futures contracts, fixed income options, interest rate swaps, total return swaps, credit default swaps, or other derivatives only if the expected risks and rewards of the derivatives are consistent with the investment objective, policies, strategies, and risks of the Portfolio as disclosed in this prospectus. The advisor will not use derivatives to change the risk exposure of the Portfolio. In particular, derivatives will be used for the Portfolio only where they may help the advisor invest in eligible asset classes with greater efficiency and lower cost than is possible through direct investment; add value when these instruments are attractively priced; adjust sensitivity to changes in interest rates; or hedge foreign currency exposure. The Portfolio will not use derivatives for speculation or for the purpose of leveraging (magnifying) investment returns.
Plain Talk About Derivatives
Derivatives can take many forms. Some forms of derivatives—such as
exchange-traded futures and options on securities, commodities, or
indexes—have been trading on regulated exchanges for decades. These
types of derivatives are standardized contracts that can easily be bought and
sold and whose market values are determined and published daily. On the
other hand, non-exchange-traded derivatives—such as certain swap
agreements—tend to be more specialized or complex and may be more
difficult to accurately value.
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The Portfolio may invest a small portion of its assets in fixed income futures, which are a type of derivative, and/or shares of exchange-traded funds (ETFs). These fixed income futures and ETFs typically provide returns similar to those of the bonds listed in the index, or in a subset of the index, the Portfolio seeks to track. The Portfolio may purchase futures or ETFs when doing so will reduce the Portfolio’s transaction costs, facilitate cash management, mitigate risk, or have the potential to add value because the instruments are favorably priced. Vanguard receives no additional revenue from Portfolio assets invested in ETF Shares of other Vanguard funds. Portfolio assets invested in ETF Shares are excluded when allocating to the Portfolio its share of the costs of Vanguard operations.
Cash Management
The Portfolio'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 Portfolio bears its proportionate share of the expenses of the CMT Fund in which it invests. Vanguard receives no additional revenue from Portfolio assets invested in a CMT Fund.
Temporary Investment Measures
The Portfolio may temporarily depart from its normal investment policies and strategies when the advisor believes that doing so is in the Portfolio's best interest, so long as the strategy or policy employed is consistent with the Portfolio's investment objective. For instance, the Portfolio may invest beyond its normal limits in derivatives or exchange-traded funds that are consistent with the Portfolio's investment objective when those instruments are more favorably priced or provide needed liquidity, as might be the case when the Portfolio receives large cash flows that it cannot prudently invest immediately.
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 an investor engaging in frequent trading, the fund incurs costs for buying and selling securities, resulting in increased brokerage and administrative costs. These costs
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are borne by all fund investors, 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 investors. Although there is no assurance that Vanguard will 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.
• Certain Vanguard funds charge investors purchase and/or redemption fees on transactions.
You may purchase or sell Portfolio shares through a contract offered by an insurance company. When insurance companies establish omnibus accounts in the Portfolio for their clients, we cannot monitor the individual clients’ trading activity. However, we review trading activity at the omnibus account level, and we look for activity that may indicate potential frequent trading or market-timing. If we detect suspicious trading activity, we will seek the assistance of the insurance company to investigate that trading activity and take appropriate action, including prohibiting additional purchases of Portfolio shares by a client. Insurance companies may apply frequent-trading policies that differ from one another. Please read the insurance company contract and program materials carefully to learn of any rules or fees that may apply.
See the accompanying prospectus for the annuity or insurance program through which Portfolio shares are offered for further details on transaction policies.
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The Portfolio, 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.
A precautionary note to investment companies: The Portfolio's shares are issued by a registered investment company, and therefore the acquisition of such shares by other investment companies and private funds is subject to the restrictions of Section 12(d)(1) of the Investment Company Act of 1940 (the 1940 Act). SEC Rule 12d1-4 under the 1940 Act permits registered investment companies to invest in other registered investment companies beyond the limits in Section 12(d)(1), subject to certain conditions, including that funds with different investment advisors must enter into a fund of funds investment agreement.
Turnover Rate
A mutual fund’s turnover rate is a measure of its trading activity. Generally, an index fund sells securities in response to redemption requests or to changes in the composition of its target index, or to manage the fund‘s duration. The Portfolio may sell securities regardless of how long they have been held. The historical turnover rates for the Portfolio can be found in the Financial Highlights section of this prospectus. A turnover rate of 100%, for example, would mean that the Portfolio 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.
The Portfolio and Vanguard
The Portfolio is a member of The Vanguard Group, Inc. (Vanguard), a family of over 200 funds. All of the funds that are members of Vanguard (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.
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Plain Talk About Vanguard’s Unique Corporate Structure
Vanguard 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
The Vanguard Group, Inc., P.O. Box 2600, Valley Forge, PA 19482, which began operations in 1975, provides investment advisory services to the Portfolio through its Fixed Income Group pursuant to the Funds' Service Agreement and subject to the supervision and oversight of the trustees and officers of Vanguard Variable Insurance Funds. As of December 31, 2022, Vanguard served as advisor for approximately $6 trillion in assets.
For the fiscal year ended December 31, 2022, the Portfolio’s advisory expenses represented an effective annual rate of 0.03% of the Portfolio’s average net assets.
Under the terms of an SEC exemption, the board of trustees of Vanguard Variable Insurance Funds 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 Portfolio’s advisory arrangements will be communicated to shareholders in writing. As the Portfolio’s sponsor and overall manager, Vanguard may provide investment advisory services to the Portfolio at any time. Vanguard may also 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. Vanguard Variable Insurance Funds 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 Portfolio may rely on the new SEC relief.
For a discussion of why the Board approved the Portfolio's investment advisory arrangement, see the most recent semiannual report to shareholders covering the fiscal period ended June 30.
The managers primarily responsible for the day-to-day management of the Portfolio are:
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Joshua C. Barrickman, CFA, Principal of Vanguard and co-head of Vanguard’s Fixed Income Indexing Americas. He has been with Vanguard since 1998, has worked in investment management since 1999, has managed investment portfolios since 2005, and has managed the Portfolio since 2013. Education: B.S., Ohio Northern University; M.B.A., Lehigh University.
Tara Talone, CFA, Portfolio Manager at Vanguard. She has been with Vanguard since 2006, has managed investment portfolios since 2018, and she has co-managed the Portfolio since September 2022. Education: B.S., Saint Joseph’s University; M.B.A., The Wharton School of the University of Pennsylvania.
The Portfolio's Statement of Additional Information provides information about each portfolio manager’s compensation, other accounts under management, and ownership of shares of the Portfolio.
Taxes
The Portfolio normally distributes its net investment income and net realized short-term or long-term capital gains, if any, to its shareholders, which are the insurance company separate accounts that fund your variable annuity or variable life insurance contract. From time to time, the Portfolio may also make distributions that are treated as a return of capital. The tax consequences to you of your investment in the Portfolio depend on the provisions of the annuity or life insurance contract through which you invest; please refer to the prospectus of such contract for more information.
The Portfolio intends to operate in such a manner that a separate account investing only in Portfolio shares will result in the variable annuity and variable life insurance contracts supported by that account receiving favorable tax treatment. This favorable treatment means that you generally will not be taxed on Portfolio distributions or proceeds on dispositions of Portfolio shares received by the separate account funding your contract. In order to qualify for this favorable treatment, the insurance company separate accounts that invest in the Portfolio must satisfy certain requirements. If a Portfolio funding your contract does not meet such requirements, your contract could lose its favorable tax treatment and income and gain allocable to your contract could be taxable to you. Also, if the IRS were to determine that contract holders have an impermissible level of control over the investments funding their contracts, your contract could lose its favorable tax treatment and income and gain allocable to your contract could be taxable currently to you. Please see the Portfolio’s Statement of Additional Information for more information.
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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, NAVs will be calculated 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. The NAV per share is computed by dividing the total assets, minus liabilities, of the Portfolio by the number of Portfolio shares outstanding. On U.S. holidays or other days when the NYSE is closed, the NAV is not calculated, and the Portfolio does not sell or redeem shares. However, on those days the value of the Portfolio’s assets may be affected to the extent that the Portfolio holds securities that change in value on those days (such as foreign securities that trade on foreign markets that are open).
Debt securities held by a Vanguard portfolio are valued based on information furnished by an independent pricing service or market quotations. When a portfolio determines that pricing-service information or 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 portfolio 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 portfolio are based on the NAVs of the shares. The values of any ETF shares or closed-end fund shares held by a portfolio are based on the market value of the shares.
A portfolio also may use fair-value pricing on bond market holidays when the portfolio is open for business (such as Columbus Day and Veterans Day). 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 portfolio to calculate the NAV may differ from quoted or published prices for the same securities.
The Portfolio has authorized certain financial intermediaries and their designees, and may, from time to time, authorize certain fund of funds for which Vanguard serves as the investment advisor (Vanguard Funds of Funds), to accept orders to buy or sell fund shares on its behalf. The Portfolio will be deemed to receive an
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order when accepted by the financial intermediary, its designee, or one of the Vanguard Funds of Funds, and the order will receive the NAV next computed by the Portfolio after such acceptance.
The Portfolio’s NAV is used to determine the unit value for the annuity or life insurance program through which you invest. For more information on unit values, please refer to the accompanying prospectus of the insurance company that offers your annuity or life insurance program.
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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.
Yields and total returns presented for the Portfolio are net of the Portfolio's operating expenses, but they do not take into account charges and expenses attributable to the annuity or life insurance program through which you invest. The expenses of the annuity or life insurance program reduce the returns and yields you ultimately receive, so you should bear those expenses in mind when evaluating the performance of the Portfolio and when comparing the yields and returns of the Portfolio with those of other mutual funds.
Vanguard Total Bond Market Index Portfolio
Year Ended December 31,
For a Share Outstanding Throughout Each Period
2022
2021
2020
2019
2018
Net Asset Value, Beginning of Period
$12.22
$12.81
$12.21
$11.54
$11.86
Investment Operations
 
 
 
 
 
Net Investment Income1
.250
.228
.277
.324
.313
Net Realized and Unrealized Gain (Loss) on Investments
(1.844)
(.454)
.635
.657
(.343)
Total from Investment Operations
(1.594)
(.226)
.912
.981
(.030)
Distributions
 
 
 
 
 
Dividends from Net Investment Income
(.226)
(.260)
(.312)
(.311)
(.267)
Distributions from Realized Capital Gains
(.080)
(.104)
(.023)
Total Distributions
(.306)
(.364)
(.312)
(.311)
(.290)
Net Asset Value, End of Period
$10.32
$12.22
$12.81
$12.21
$11.54
Total Return
-13.21%
-1.72%
7.58%
8.67%
-0.21%
Ratios/Supplemental Data
 
 
 
 
 
Net Assets, End of Period (Millions)
$3,972
$4,871
$4,867
$4,300
$3,535
Ratio of Total Expenses to Average Net Assets
0.14%2
0.14%
0.14%
0.14%
0.14%
Ratio of Net Investment Income to Average Net Assets
2.30%
1.85%
2.20%
2.72%
2.74%
Portfolio Turnover Rate3
42%
69%
94%
80%
89%
 
 
1
Calculated based on average shares outstanding.
2
The ratio of expenses to average net assets for the period net of reduction from custody fee offset arrangements
was 0.14%.
3
Includes 12%, 33%, 28%, 19%, and 26%, respectively, attributable to mortgage-dollar-roll activity.
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23

General Information
This Portfolio of Vanguard Variable Insurance Funds offers its shares to insurance companies to fund both annuity and life insurance contracts. Because of differences in tax treatment or other considerations, the best interests of various contract owners participating in the Portfolio might at some time be in conflict. The Board will monitor for any material conflicts and determine what action, if any, should be taken.
If the Board determines that continued offering of shares would be detrimental to the best interests of the Portfolio’s shareholders, the Portfolio may suspend the offering of shares for a period of time. If the Board determines that a specific purchase acceptance would be detrimental to the best interests of the Portfolio’s shareholders (for example, because of the size of the purchase request or a history of frequent trading by the investor), the Portfolio may reject such a purchase request.
If you wish to redeem money from the Portfolio, please refer to the instructions provided in the accompanying prospectus for the annuity or life insurance program. Shares of the Portfolio may be redeemed on any business day that the NYSE is open for trading. The redemption price of shares will be at the next-determined NAV per share. Redemption proceeds generally will be wired to the administrator within one business day following receipt of the redemption request, but no later than seven business days. Contract owners will receive their redemption checks from the administrator.
Under normal circumstances, the Portfolio typically expects to meet redemptions with positive cash flows. When this is not an option, the Portfolio seeks maintain its risk exposure by selling a cross section of the Portfolio’s holdings to meet redemptions, while also factoring in transaction costs. Additionally, the Portfolio may work with the insurance companies through which contract owners participate in the Portfolio to implement redemptions in a manner that is least disruptive to the portfolio.
Under certain circumstances, including under stressed market conditions, there are additional tools that the Portfolio 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 Portfolio may also suspend payment of redemption proceeds for up to seven days. Additionally, under these unusual circumstances, the Portfolio may borrow money (subject to certain regulatory conditions and if available under board-approved procedures) through an interfund lending facility; through a bank line-of-credit, including a joint committed credit facility; or through an uncommitted line-of-credit from Vanguard in order to meet redemption requests.
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The Portfolio may suspend the redemption right or postpone payment at times when the NYSE is closed or during any emergency circumstances, as determined by the SEC.
The exchange privilege (your ability to redeem shares from one Portfolio to purchase shares of another Portfolio) may be available to you through your contract. Although we make every effort to maintain the exchange privilege, Vanguard reserves the right to revise or terminate this privilege, limit the amount of an exchange, or reject any exchange, at any time, without notice.
The Portfolio may pay redemption proceeds, in whole or in part, by an in-kind distribution of readily marketable securities if Vanguard determines that it would be detrimental to the best interests of the Portfolio's remaining shareholders to pay redemption proceeds in cash.
For certain categories of investors, the Portfolio has authorized one or more brokers to accept on its behalf purchase and redemption orders. The brokers are authorized to designate other intermediaries to accept purchase and redemption orders on the Portfolio’s behalf. The Portfolio will be deemed to have received a purchase or redemption order when an authorized broker, or a broker’s authorized designee, accepts the order in accordance with the Portfolio’s instructions. In most cases, for these categories of investors, a contract owner’s properly transmitted order will be priced at the Portfolio’s next-determined NAV after the order is accepted by the authorized broker or the broker’s designee. The contract owner should review the authorized broker’s policies relating to trading in the Vanguard funds.
Please consult the Portfolio’s Statement of Additional Information or our website for a description of the policies and procedures that govern disclosure of the Portfolio's portfolio holdings.
The Portfolio's Bylaws require, unless the Trust otherwise consents in writing, that the U.S. Federal District Courts be the sole and exclusive forum for the resolution of complaints under the Securities Act of 1933. This provision may limit a shareholder’s ability to bring a claim in a different forum and may result in increased shareholder costs in pursuing such a claim.
Shareholder Rights
The Portfolio's Agreement and Declaration of Trust, as amended, requires a shareholder bringing a derivative action on behalf of Vanguard Variable Insurance Funds (the Trust) that is subject to a pre-suit demand to collectively hold at least 10% of the outstanding shares of the Trust or at least 10% of the outstanding
25

shares of the series or class to which the demand relates and to undertake to reimburse the Trust for the expense of any counsel or advisors used when considering the merits of the demand in the event that the board of trustees determines not to bring such action. In each case, these requirements do not apply to claims arising under the federal securities laws to the extent that any such federal securities laws, rules, or regulations do not permit such application.
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CFA® is a registered trademark owned by CFA Institute.
”Bloomberg®” and the Bloomberg U.S. Aggregate Float Adjusted Index (the Index or Bloomberg Index) are service marks of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited (“BISL”), the administrator of the Index (collectively, “Bloomberg”), and have been licensed for use for certain purposes by Vanguard.
The Total Bond Market Index Portfolio is not sponsored, endorsed, sold or promoted by Bloomberg. Bloomberg does not make any representation or warranty, express or implied, to the owners of or counterparties to the Total Bond Market Index Portfolio or any member of the public regarding the advisability of investing in securities generally or in the Total Bond Market Index Portfolio particularly. The only relationship of Bloomberg to Vanguard is the licensing of certain trademarks, trade names and service marks and of the Bloomberg U.S. Aggregate Float Adjusted Index, which is determined, composed and calculated by BISL without regard to Vanguard or the Total Bond Market Index Portfolio. Bloomberg has no obligation to take the needs of Vanguard or the owners of the Total Bond Market Index Portfolio into consideration in determining, composing or calculating the Bloomberg U.S. Aggregate Float Adjusted Index. Bloomberg is not responsible for and has not participated in the determination of the timing of, prices at, or quantities of the Total Bond Market Index Portfolio to be issued. Bloomberg shall not have any obligation or liability, including, without limitation, to the Total Bond Market Index Portfolio customers, in connection with the administration, marketing or trading of the Total Bond Market Index Portfolio.
BLOOMBERG DOES NOT GUARANTEE THE ACCURACY AND/OR THE COMPLETENESS OF THE BLOOMBERG U.S. AGGREGGATE FLOAT ADJUSTED INDEX OR ANY DATA RELATED THERETO AND SHALL HAVE NO LIABILITY FOR ANY ERRORS, OMISSIONS OR INTERRUPTIONS THEREIN. BLOOMBERG DOES NOT MAKE ANY WARRANTY, EXPRESS OR IMPLIED, AS TO RESULTS TO BE OBTAINED BY VANGUARD, OWNERS OF THE TOTAL BOND MARKET INDEX PORTFOLIO OR ANY OTHER PERSON OR ENTITY FROM THE USE OF THE BLOOMBERG U.S. AGGREGGATE FLOAT ADJUSTED INDEX OR ANY DATA RELATED THERETO. BLOOMBERG DOES NOT MAKE ANY EXPRESS OR IMPLIED WARRANTIES AND EXPRESSLY DISCLAIMS ALL WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE WITH RESPECT TO THE BLOOMBERG U.S. AGGREGGATE FLOAT ADJUSTED INDEX OR ANY DATA RELATED THERETO. WITHOUT LIMITING ANY OF THE FOREGOING, TO THE MAXIMUM EXTENT ALLOWED BY LAW, BLOOMBERG, ITS LICENSORS, AND ITS AND THEIR RESPECTIVE EMPLOYEES, CONTRACTORS, AGENTS, SUPPLIERS, AND VENDORS SHALL HAVE NO LIABILITY OR RESPONSIBILITY WHATSOEVER FOR ANY INJURY OR DAMAGES—WHETHER DIRECT, INDIRECT, CONSEQUENTIAL, INCIDENTAL, PUNITIVE OR OTHERWISE—ARISING IN CONNECTION WITH THE TOTAL BOND MARKET INDEX PORTFOLIO OR BLOOMBERG U.S. AGGREGGATE FLOAT ADJUSTED INDEX OR ANY DATA OR VALUES RELATING THERETO—WHETHER ARISING FROM THEIR NEGLIGENCE OR OTHERWISE, EVEN IF NOTIFIED OF THE POSSIBILITY THEREOF.
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Glossary of Investment Terms
Average Maturity. The average length of time until bonds held by a portfolio reach maturity and are repaid. In general, the longer the average maturity, the more a portfolio's share price fluctuates in response to changes in market interest rates. In calculating average maturity, a portfolio uses a bond’s maturity or, if applicable, an earlier date on which the advisor believes it is likely that a maturity-shortening device (such as a call, put, refunding, prepayment, or redemption provision or an adjustable coupon rate) will cause the bond to be repaid.
Bond. A debt security (IOU) issued by a corporation, a government, or a government agency in exchange for the money the bondholder lends it. In most instances, the issuer agrees to pay back the loan by a specific date and generally to make regular interest payments until that date.
Capital Gains Distributions. Payments to portfolio shareholders of gains realized on securities that a portfolio 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.
Corporate Bond. An IOU issued by a business that wants to borrow money. As with other types of bonds, the issuer promises to repay the borrowed money by a specific date and generally to make interest payments in the meantime.
Coupon Rate. The interest rate paid by the issuer of a debt security until its maturity. It is expressed as an annual percentage of the face value of the security.
Dividend Distributions. Payments to portfolio shareholders of income from interest or dividends generated by a portfolio's investments.
Expense Ratio. A portfolio's total annual operating expenses expressed as a percentage of the portfolio'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.
Face Value. The amount to be paid at a bond’s maturity; also known as the par value or principal.
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Fixed Income Security. An investment, such as a bond, representing a debt that must be repaid by a specified date, and on which the borrower may pay a fixed, variable, or floating rate of interest.
Float-Adjusted Index. An index that weights its constituent securities based on the value of the constituent securities that are available for public trading, rather than the value of all constituent securities. Some portion of an issuer’s securities may be unavailable for public trading because, for example, those securities are owned by company insiders on a restricted basis or by a government agency. By excluding unavailable securities, float-adjusted indexes can produce a more accurate picture of the returns actually experienced by investors in the measured market.
Inception Date. The date on which the assets of a portfolio are first invested in accordance with the portfolio's investment objective. For portfolios with a subscription period, the inception date is the day after that period ends. Investment performance is generally measured from the inception date.
Indexing. A low-cost investment strategy in which a portfolio attempts to track—rather than outperform—a specified market benchmark, or “index.”
International Dollar-Denominated Bond. A bond denominated in U.S. dollars issued by foreign governments and companies. Because the bond’s value is designated in dollars, an investor is not exposed to foreign-currency risk.
Investment-Grade Bond. A debt security whose credit quality is considered by independent bond rating agencies, or through independent analysis conducted by a portfolio's advisor, to be sufficient to ensure timely payment of principal and interest under current economic circumstances. Debt securities rated in one of the four highest rating categories are considered investment-grade. Other debt securities may be considered by an advisor to be investment-grade.
Joint Committed Credit Facility. The Portfolio 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 Portfolio's board of trustees and renegotiation with the lender syndicate on an annual basis.
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Mortgage-Backed Security. A bond or pass-through certificate that represents an interest in an underlying pool of mortgages and is issued by various government agencies or private corporations. Unlike ordinary fixed income securities, mortgage-backed securities include both interest and principal as part of their regular payments.
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.
Principal. The face value of a debt instrument or the amount of money put into an investment.
Return of Capital. A return of capital occurs when a portfolio's distributions exceed its earnings in a fiscal year. A return of capital is a return of all or part of your original investment or amounts paid in excess of your original investment in a portfolio. In general, a return of capital reduces your cost basis in a portfolio's shares and is not taxable to you until your cost basis has been reduced to zero.
Securities. Stocks, bonds, money market instruments, and other investments.
Total Return. A percentage change, over a specified time period, in a portfolio'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 portfolio'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.
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For More Information
If you would like more information about Vanguard Variable Insurance Funds Total Bond Market Index Portfolio, the following documents are available free upon request:
Annual/Semiannual Reports to Shareholders
Additional information about the Portfolio's investments is available in the Portfolio's annual and semiannual reports to shareholders. In the annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
Statement of Additional Information (SAI)
The SAI provides more detailed information about the Portfolio and is incorporated by reference into (and thus legally a part of) this prospectus.
To receive a free copy of the latest annual or semiannual reports or the SAI, or to request additional information about the Portfolio or other Vanguard funds, please visit vanguard.com or contact us as follows:
Telephone: 800-522-5555; Text telephone for people with hearing impairment: 800-749-7273
Information Provided by the SEC
Reports and other information about the Portfolio are available in the EDGAR database on the SEC’s website at sec.gov, or you can receive copies of this information, for a fee, by electronic request at the following email address: [email protected].
Portfolio's Investment Company Act file number: 811-05962
© 2023 The Vanguard Group, Inc. All rights reserved.
Vanguard Marketing Corporation, Distributor.
P 257 042023