PIMCO Variable Insurance Trust
Prospectus
April 28, 2023
Share Class: Institutional
REAL RETURN STRATEGY PORTFOLIO
PIMCO Real Return Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
Neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

Table of Contents


PIMCO Real Return Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with preservation of real capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.50%
Other Expenses (1)
0.12%
Total Annual Portfolio Operating Expenses
0.62%
1
“Other Expenses” include interest expense of 0.12%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.50% for Institutional Class shares.
Example. The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then hold or redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$63
$199
$346
$774
Portfolio Turnover
The Portfolio pays transaction costs 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 the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 97 % of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its net assets in inflation-indexed bonds of varying maturities issued by the U.S. and non-U.S. governments, their agencies or instrumentalities and corporations, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. Assets not invested in inflation-indexed bonds may be invested in other types of Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. Inflation-indexed bonds are fixed income securities that are structured to provide protection against inflation. The value of the bond’s principal or the interest income paid on the bond is adjusted to track changes in an official inflation measure. The U.S. Treasury uses the Consumer Price Index for Urban Consumers as the inflation measure. Inflation-indexed bonds issued by a foreign government are generally adjusted to reflect a comparable inflation index, calculated by that government. “Real return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Effective duration, a common method of calculating duration, takes into account that for certain bonds expected cash flows will fluctuate as interest rates change and is defined in nominal yield terms, which is market convention for most bond investors and managers. Because market convention for bonds is to use nominal yields to measure effective duration, effective duration for real return bonds, which are based on real yields, are converted through a conversion factor. The resulting nominal duration typically can range from 20% and 90% of the respective real duration. All security holdings will be measured in nominal effective duration terms. Similarly, the effective duration of the Bloomberg U.S. TIPS Index will be calculated using the same conversion factors. The effective duration of this Portfolio normally varies within three years (plus or minus) of the effective duration of the securities comprising the Bloomberg U.S. TIPS Index, as calculated by PIMCO, which as of February 28, 2023 was 7.01 years.
The Portfolio invests primarily in investment grade securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”) rated B or higher by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality (except that within such 10% limitation, the Portfolio may invest in mortgage-related securities rated below B). In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio also may invest up to 30% of its total assets in securities denominated in foreign currencies and may invest beyond this limit in U.S. dollar denominated securities of foreign issuers. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt

PIMCO Variable Insurance Trust | Prospectus 1

PIMCO Real Return Portfolio

denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk: the risk that fixed income securities will fluctuate in value because of a change in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk: the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons ( e.g ., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk: the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk: the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk: the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk: the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, changes in financial condition or credit rating, financial leverage or reduced demand for the issuer’s goods or services
Liquidity Risk: the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk: the risk of investing in derivative instruments (such as forwards, futures, swaps and structured securities) and other similar investments, including leverage, liquidity, interest rate, market, counterparty (including credit), operational, legal and management risks, and valuation complexity. Changes in the value of a derivative or other similar investments may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. Changes in the value of a derivative or other similar instrument may also create margin delivery or settlement payment obligations for the Portfolio. The Portfolio’s use of derivatives or other similar investments may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives or other similar investments are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives or other similar investments. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a registered fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives or other similar investments and/or adversely affect the value of derivatives or other similar investments and the Portfolio’s performance
Equity Risk: the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk: the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk

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Foreign (Non-U.S.) Investment Risk: the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes, diplomatic developments or the imposition of sanctions and other similar measures. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk: the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk: the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk: the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk: the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk: the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio managers in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Inflation-Indexed Security Risk: the risk that inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the principal and interest are adjusted for inflation. There can be no assurance that the inflation index used will accurately measure the real rate of inflation in the prices of goods and services. Any increase in the principal amount of an
inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity
Short Exposure Risk: the risk of entering into short sales or other short positions, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale or other short positions will not fulfill its contractual obligations, causing a loss to the Portfolio
Collateralized Loan Obligations Risk: the risk that investing in collateralized loan obligations (“CLOs”) and other similarly structured investments exposes the Portfolio to heightened credit risk, interest rate risk, liquidity risk, market risk and prepayment and extension risk, as well as the risk of default on the underlying asset. In addition, investments in CLOs carry additional risks including, but not limited to, the risk that: (i) distributions from the collateral may not be adequate to make interest or other payments; (ii) the quality of the collateral may decline in value or default; (iii) the Portfolio may invest in tranches of CLOs that are subordinate to other tranches; (iv) the structure and complexity of the transaction and the legal documents could lead to disputes among investors regarding the characterization of proceeds; and (v) the CLO’s manager may perform poorly
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. 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.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg U.S. TIPS Index is an unmanaged market index comprised of all U.S. Treasury Inflation-Protected Securities rated investment grade (Baa3 or better), having at least one year to final maturity, and at least $500 million par amount outstanding.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit .

April 28, 2023 | Prospectus 3

PIMCO Real Return Portfolio


Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
5.33%
Worst Quarter
June 30, 2013
-8.41%
Average Annual Total Returns (for periods ended 12/31/22)
 
1 Year
5 Years
10 Years
Institutional Class Return
-11.77%
2.11%
1.05%
Bloomberg U.S. TIPS Index (reflects no deductions for
fees, expenses or taxes)
-11.85%
2.11%
1.12%
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Steve Rodosky and Daniel He. Mr. Rodosky is a Managing Director of PIMCO, and he has managed the Portfolio since January 2019. Mr. He is an Executive Vice President of PIMCO, and he has managed the Portfolio since December 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts ( i.e. , variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will fluctuate in value because of a change in interest rates. For example, as nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds , including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities , a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments. Risks associated with rising interest rates are heightened under current market conditions given that the U.S. Federal Reserve (the “Federal Reserve”) has begun to raise interest rates from historically low levels and has signaled an intention to continue to do so. Further, in market environments where interest rates are rising, issuers may be less willing or able to make principal and interest payments on fixed-income investments when due.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Certain European countries have previously experienced negative interest rates on certain fixed income instruments . Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration , meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons ( e.g. , declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The risk that such issuer, guarantor or counterparty is less willing or able to do so is heightened in market environments where interest rates are rising. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest. Rising or high interest rates may deteriorate the credit quality of an issuer or counterparty, particularly if an issuer or counterparty faces challenges rolling or refinancing its obligations.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities . In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities , an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities . Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.

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In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, social unrest, recessions, supply chain disruptions, market manipulation, government defaults, government shutdowns, political changes, diplomatic developments or the imposition of sanctions and other similar measures, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities . As discussed more under “Interest Rate Risk,” the Federal Reserve has begun to raise interest rates from historically low levels and has signaled an intention to continue to do so. Any additional interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, major litigation, investigations or other controversies, changes in financial condition or credit rating, changes in government regulations affecting the issuer or its competitive environment and strategic initiatives such as mergers, acquisitions or dispositions and the market response to any such initiatives, financial leverage or reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission (the “SEC”) defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make

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PIMCO Variable Insurance Trust

markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities , Rule 144A securities, illiquid sectors of fixed income securities , derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives and other similar instruments (referred to collectively as “derivatives”) are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives ), interest rate risk, market risk, leverage risk, counterparty (including credit) risk, operational risk, legal risk and management risk, as well as risks arising from changes in applicable requirements, risks arising from margin requirements and risks arising from mispricing or valuation complexity. They also involve the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. The Portfolio may be required to hold additional cash or sell other investments in order to obtain cash to close out a position and changes in the value of a derivative may also create margin delivery or settlement payment obligations for the Portfolio. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives . The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other

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Prospectus

economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives , or may otherwise adversely affect the value or performance of derivatives . Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio’s investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also,

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nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions, diplomatic developments or the imposition of sanctions or other similar measures could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities . The type and severity of sanctions and other similar measures, including counter sanctions and other retaliatory actions, that may be imposed could vary broadly in scope, and their impact is difficult to ascertain. These types of measures may include, but are not limited to, banning a sanctioned country or certain persons or entities associated with such country from global payment systems that facilitate cross-border payments, restricting the settlement of securities transactions by certain investors, and freezing the assets of particular countries, entities or persons. The imposition of sanctions and other similar measures could, among other things, result in a decline in the value and/or liquidity of securities issued by the sanctioned country or companies located in or economically tied to the sanctioned country, downgrades in the credit ratings of the sanctioned country's securities or those of companies located in or economically tied to the sanctioned country, currency devaluation or volatility, and increased market volatility and disruption in the sanctioned country and throughout the world. Sanctions and other similar measures could directly or indirectly limit or prevent the Portfolio from buying and selling securities (in the sanctioned country and other markets), significantly delay or prevent the settlement of securities transactions, and adversely impact the Portfolio's liquidity and performance. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities . Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio will also be subject to Emerging Markets Risk to the extent it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies , or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies , it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities , and the use of when-issued, delayed delivery or forward commitment transactions . The use of derivatives may also create leveraging risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy its obligations when it may not be advantageous to do so. Leverage, including borrowing , may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box” ( i.e ., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration), could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so. Leveraging transactions pursued by the Portfolio may increase its duration and sensitivity to interest rate movements.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systemic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Inflation-Indexed Security Risk
Inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Thus generally, during periods of rising inflation, the value of inflation-indexed securities will tend to increase and during periods of deflation, their value will tend to decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the principal and interest are adjusted for inflation. There can be no assurance that the inflation index used ( i.e. , the CPI), which is calculated and

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published by a third-party, will accurately measure the real rate of inflation in the prices of goods and services. Increases in the principal value of TIPS due to inflation are considered taxable ordinary income for the amount of the increase in the calendar year. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity. Additionally, a CPI swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap. With municipal inflation-indexed securities, the inflation adjustment is integrated into the coupon payment, which is federally tax exempt (and may be state tax exempt). For municipal inflation-indexed securities, there is no adjustment to the principal value. Because municipal inflation-indexed securities are a small component of the municipal bond market, they may be less liquid than conventional municipal bonds.
Short Exposure Risk
The Portfolio’s short sales and short positions, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale or short position will not fulfill its contractual obligations, causing a loss to the Portfolio.
Collateralized Loan Obligations Risk
The Portfolio may invest in collateralized loan obligation (“CLOs”) and other similarly structured investments. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. The Portfolio’s investments in CLOs and other similarly structured investments may expose the Portfolio to heightened credit risk, interest rate risk, liquidity risk, market risk and prepayment and extension risk, as well as the risk of default on the underlying asset. In addition, investments in CLOs carry additional risks including, but not limited to, the risk that: (i) distributions from the collateral may not be adequate to make interest or other payments; (ii) the quality of the collateral may decline in value or default; (iii) the Portfolio may invest in tranches of CLOs that are subordinate to other tranches; (iv) the structure and complexity of the transaction and the legal documents could lead to disputes among investors regarding the characterization of proceeds; and (v) the CLO’s manager may perform poorly CLOs may charge management and other administrative fees, which are in addition to those of the Portfolio.
The cash flows from a CLO are split into two or more portions, called tranches, varying in risk and yield. The riskiest portion is the “equity” tranche which bears the bulk of defaults from the bonds or loans in the trust and serves to protect the other, more senior tranches from default in all but the most severe circumstances. Since they are partially protected from defaults, senior tranches from a CLO typically have higher ratings and lower yields than their underlying securities, and can be rated investment grade. Despite the protection from the equity tranche, CLO tranches can experience substantial losses due to actual defaults, increased sensitivity to defaults due to collateral default and disappearance of protecting tranches, market anticipation of defaults, as well as aversion to CLO securities as a class. The risks of an investment in a CLO depend largely on the type of the collateral securities and the class of the instrument in which the Portfolio invests. Typically, CLOs are privately offered and sold, and thus, are not registered under the securities laws.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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Prospectus

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees (the “Board”) of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2022, PIMCO had approximately $1.74 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2022, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee. The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2022, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board’s approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2022.
Supervisory and Administrative Fee. The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational and offering expenses of the Trust and the Portfolio, and any other expenses which are capitalized in accordance with generally accepted accounting principles, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2022, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2024, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) within thirty-six months of the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Real Return
Daniel He
12/19
Executive Vice President, PIMCO. Mr. He is a portfolio manager in the Newport Beach office.
He is a member of the liquid products group specializing in real return and mortgage-backed
securities. Prior to joining PIMCO in 2011, he structured and traded derivative strategies for
a global macro hedge fund. He previously developed trading strategies at a hedge fund that
focused on foreign exchange volatility. He has investment experience since 2005 and holds
an MBA from the University of Chicago Booth School of Business. He also holds a master's
degree in financial engineering and an undergraduate degree in computer science from the
National University of Singapore.
PIMCO Real Return
Steve Rodosky
1/19
Managing Director, PIMCO. Mr. Rodosky is a managing director in the Newport Beach office
and a portfolio manager for real return and U.S. long duration strategies. He leads the rates
liquid products team and also leads talent management for portfolio management in the
U.S. Prior to joining PIMCO in 2001, Mr. Rodosky was vice president of institutional sales
with Merrill Lynch. He has 28 years of investment experience and holds a master's degree in
financial markets from Illinois Institute of Technology. He received an undergraduate degree
from Villanova University.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the SEC.

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Prospectus

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements. Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments
Account Services. PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies, including their affiliates, for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. The fees paid to insurance companies will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis. Although these payments are not intended to compensate the insurance companies or their affiliates for marketing the Portfolio, the payments may provide an additional incentive to insurance companies or their affiliates to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or share classes of the Portfolio) available under a particular Variable Contract. Additionally, although these payments are made out of PIMCO’s own resources, in some cases the levels of such payments may vary by Portfolio or share class in relation to advisory fees, total annual operating expenses or other payments made by the Portfolio or share class to PIMCO. These payments, taken together in the aggregate, may be material to financial firms relative to other compensation paid by the Portfolio and/or PIMCO and may be in addition to any (a) distribution
and/or servicing (12b-1) fees; (b) marketing support, revenue sharing or “shelf space” fees; and (c) event support, other noncash compensation and charitable contributions, as described below and paid to or at the request of such financial firms or their personnel.
Revenue Sharing/Marketing Support. In addition, the Distributor or PIMCO (for purposes of the remainder of this subsection only, collectively “PIMCO”) makes payments and provides other incentives to insurance companies as compensation for services such as providing the Portfolio with “shelf space,” or a higher profile for the insurance companies’ financial professionals and their customers, placing the Portfolio on the insurance companies’ referred or recommended fund list or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes whose distributor or investment adviser is not making such payments, granting PIMCO access to the insurance companies’ financial professionals (including through the insurance companies’ intranet websites or other proprietary communications systems and channels) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as on the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies and their affiliates.

A number of factors are considered in determining the amount of these additional payments to insurance companies and/or their affiliates. On some occasions, such payments may be conditioned upon levels of sales over a particular period, including the sale of a specified minimum dollar amount of the shares of the Portfolio and/or all of the portfolios and/or other funds sponsored by PIMCO together or a particular class of shares, during a specified period of time. PIMCO also makes payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with PIMCO and/or its affiliates.
Event Support; Other Non-Cash Compensation; Charitable Contributions. In addition to the payments described above, PIMCO pays and/or reimburses, at its own expense insurance companies, their affiliates or other financial firms for sponsorship of and/or attendance at conferences, seminars or informational meetings (which may include events held through video technology, to the extent permitted by applicable regulation) (“event support”), provides financial firms or their personnel with occasional tickets to events or other entertainment (which, in some instances, is held virtually), meals and small gifts and pays or provides reimbursement for

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PIMCO Variable Insurance Trust

reasonable travel and lodging expenses for attendees of PIMCO educational events (“other non-cash compensation”), and makes charitable contributions to valid charitable organizations at the request of financial firms (“charitable contributions”) to the extent permitted by applicable law, rules and regulations.
Visits; Training; Education. In addition to the payments described above, wholesale representatives and employees of PIMCO or its affiliates visit financial firms on a regular basis to educate financial professionals and other personnel about the Portfolio and to encourage the sale or recommendation of Portfolio shares to their clients. PIMCO may also provide (or compensate consultants or other third parties to provide) other relevant training and education to a financial firm’s financial professionals and other personnel.
Consultant Services. PIMCO may pay investment consultants or their affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for PIMCO’s attendance at investment forums sponsored by such firms (collectively, “consultant services”).
Payments. Payments for items including event support and data, as well as revenue sharing, are, in certain circumstances, bundled and allocated among these categories in PIMCO’s discretion. The financial firms receiving such bundled payments may characterize or allocate the payments differently from PIMCO’s internal allocation. In addition, payments made by PIMCO to a financial firm and allocated by PIMCO to a particular category of services can in some cases result in benefits related to, or enhance the eligibility of PIMCO or the Portfolio to receive, services provided by the financial firm that may be characterized or allocated to one or more other categories of services. In addition, PIMCO pays certain expenses, which may be a flat fee by the Portfolio or share class, such as set-up fees, and printing and mailing charges, incurred by such insurance companies, including their affiliates, in connection with the services described above. These additional servicing payments and set-up fees may differ depending on the Portfolio and share class and may vary from amounts paid to the Trust’s transfer agent for providing similar services to other accounts.

The additional payments described above are made from PIMCO’s (or its affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies, their affiliates or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by PIMCO) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

The SAI contains further details about the payments made by
PIMCO to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly ( i.e. , through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Board and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of

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Prospectus

management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemptions or postpone payments for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending on various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs

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PIMCO Variable Insurance Trust

that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transaction if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of any restrictions or rejections of transactions may vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotations are readily available are valued at market value. A market quotation is readily available only when that quotation is a quoted price (unadjusted) in active markets for identical investments that the Portfolio can access at the measurement date, provided that a quotation will not be readily available if it is not reliable. Market value is generally determined on the basis of official closing prices or the last reported sales prices. The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Investments for which market quotations are not readily available are valued at fair value as determined in good faith pursuant to Rule 2a-5 under the 1940 Act. As a general principle, the fair value of a security or other asset is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Pursuant to Rule 2a-5, the Board has designated PIMCO as the valuation designee (“Valuation Designee”) for the Portfolio to perform the fair value determination relating to all Portfolio investments. PIMCO may carry out its designated responsibilities as Valuation Designee through various teams and committees. The Valuation Designee’s policies and procedures govern the Valuation Designee’s selection and application of methodologies for determining and calculating the fair value of Portfolio investments. The Valuation Designee may value Portfolio securities for which market quotations are not readily available and other Portfolio assets utilizing inputs from pricing services, quotation reporting systems, valuation agents and other third-party sources (together, “Pricing Sources”). Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Sources using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Sources may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies, other than exchange-traded funds (“ETFs”), the Portfolio’s NAV will be calculated based on the NAVs of such investments.

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Prospectus

If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value. Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Sources, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Valuation Designee may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, unless otherwise determined by the Valuation Designee, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Sources. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Fair valuation may require subjective determinations about the value of a security. While the Trust’s and Valuation Designee's policies and procedures are intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the

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professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to portfolios of any size, such risks are heightened in portfolios with fewer assets under management. In addition, new portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on
behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other
shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;

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delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond fund with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond fund with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of
U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors ( i.e. , not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the long-term effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its municipal bonds at attractive prices or value municipal bonds. The value of certain municipal

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securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk. The use of tender option bonds typically will impact the Portfolio's duration and cause the Portfolio to be subject to increased duration and interest rate risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The value of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related

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securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued
mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt

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obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio managers believe the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company
securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”

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  Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus the Consumer Price Index. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as
“catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion of or its entire principal invested in the bond or notional amount on a swap. Event-linked exposures often provide for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic

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securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects.
In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in
exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instrument is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instrument is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i)

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if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of the imposition of sanctions and other similar measures, nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities.
Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities. The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. The Portfolio is subject to the limitation on investment in emerging market
securities noted in the Portfolio Summary. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of

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securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to the imposition of sanctions and other similar measures, price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions. The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the
Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. To the extent foreign exchange transactions for the Portfolio are directed to the Portfolio’s custodian for execution, execution of such transactions may be better or worse than comparable transactions effected by other intermediaries. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated.
Redenomination. Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur

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additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements in which the Portfolio purchases a security from a bank or broker-dealer that agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivatives and other similar instruments (referred to collectively as “derivatives”) for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ
any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap. A CPI swap is a fixed maturity, OTC derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk. Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Counterparty Risk (including Credit Risk). The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based. Counterparty risk also refers to the risks of having concentrated exposure to a counterparty.

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Market and Portfolio Liquidity Risk. Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price. Liquidity risk also refers to the risk that the Portfolio may be required to hold additional cash or sell other investments in order to obtain cash to close out derivatives or meet the liquidity demands that derivatives can create to make payments of margin, collateral, or settlement payments to counterparties. The Portfolio may have to sell a security at a disadvantageous time or price to meet such obligations.
Leverage Risk. Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. Leveraging transactions pursued by the Portfolio may increase its duration and sensitivity to interest rate movements.
Lack of Availability. Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk. In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected
in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks. Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing and/or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. Also, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Operational and Legal Risk. Using derivatives is also subject to operational and legal risks. Operational risk generally refers to risk related to potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls, and human

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error. Legal risk generally refers to insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange ( e.g. , the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The timing and character of income and gains derived by the Portfolio from investments in ETNs may be affected by future legislation. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase or sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of
leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made. When the Portfolio has sold a security on a when-issued, delayed-delivery or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed-delivery or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act, and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Regulatory changes adopted by the SEC concerning investments by registered investment companies in the securities of other registered investment companies may, among other things, affect the Portfolio's ability to utilize the Central Funds. This could adversely impact the Portfolio's investment strategies and operations. The “Investment Objectives and Policies - Regulatory Risk” section in the SAI discusses these changes in further detail.

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Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e. , securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid ( i.e. , classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When the portfolio managers deem it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover ( e.g. , an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.

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Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and higher-rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events from outside threat actors or internal resources that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems ( e.g. , through “hacking” or malicious software coding), and may come from multiple sources, including outside attacks such as denial-of-service attacks ( i.e. , efforts to make network services unavailable to intended users) or cyber extortion, including exfiltration of data held for ransom and/or “ransomware” attacks that renders systems inoperable until ransom is paid, or insider actions. In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, vendors, suppliers, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches or extortion of company data. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; third party claims in litigation; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolio does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. Such entities have experienced cyber attacks

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PIMCO Variable Insurance Trust

and other attempts to gain unauthorized access to systems from time to time, and there is no guarantee that efforts to prevent or mitigate the effects of such attacks or other attempts to gain unauthorized access will be successful. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders may suffer losses as a result of a cyber security breach related to the Portfolio, its service providers, trading counterparties or the issuers in which the Portfolio invests.
Regulatory Changes Risk
Financial entities, such as investment companies and investment advisers, are generally subject to extensive government regulation and intervention. Government regulation and/or intervention may change the way the Portfolio is regulated, affect the expenses incurred directly by the Portfolio and the value of its investments, and limit and/or preclude the Portfolio’s ability to achieve its investment objective. Government regulation may change frequently and may have significant adverse consequences. The Portfolio and the investment adviser have historically been eligible for exemptions from certain regulations. However, there is no assurance that the Portfolio and the investment adviser will continue to be eligible for such exemptions. Actions by governmental entities may also impact certain instruments in which the Portfolio invests.
Moreover, government regulation may have unpredictable and unintended effects. Legislative or regulatory actions to address perceived liquidity or other issues in fixed income markets generally, or in particular markets such as the municipal securities market, may alter or impair the Portfolio’s ability to pursue its investment objectives or utilize certain investment strategies and techniques.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions (c)
 
 
 
 
Selected Per Share Data for
the Year Ended^:
Net Asset Value
Beginning of
Year (a)
Net Investment
Income (Loss) (b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Real Return Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2022
$ 13.99
$ 0.91
$ (2.51)
$ (1.60)
$ (0.90)
$ 0.00
$ 0.00
$ (0.90)
12/31/2021
13.92
0.74
0.04
0.78
(0.71)
0.00
0.00
(0.71)
12/31/2020
12.64
0.19
1.30
1.49
(0.21)
0.00
0.00
(0.21)
12/31/2019
11.85
0.24
0.77
1.01
(0.22)
0.00
0.00
(0.22)
12/31/2018
12.42
0.34
(0.59)
(0.25)
(0.32)
0.00
0.00
(0.32)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio. Additionally, excludes initial sales charges and contingent deferred sales charges.

36  Prospectus | PIMCO Variable Insurance Trust

Prospectus

 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year (a)
Total
Return (d)
Net Assets End of
Year
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 11.49
(11.85)%
$ 200,491
0.62%
0.62%
0.50%
0.50%
7.26%
97%
13.99
5.74
233,090
0.52
0.52
0.50
0.50
5.30
162
13.92
11.88
199,783
0.69
0.69
0.50
0.50
1.39
240
12.64
8.60
189,206
1.38
1.38
0.50
0.50
1.96
231
11.85
(2.06)
180,506
1.27
1.27
0.50
0.50
2.80
234

April 28, 2023 | Prospectus 37

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securities are those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securities are those rated in one of the four highest rating categories, or, if unrated, deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”), are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of eleven months or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) or similar programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim ( e.g. , senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued ( e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located ( e.g. , KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term debt obligations relative to other domestic issuers or issuances.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term debt obligations relative to other domestic issuers or issuances.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term debt obligations relative to other domestic issuers or issuances.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term debt obligations relative to other domestic issuers or issuances.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 28, 2023 | Prospectus   A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within the next five business days in the absence of a stated grace period or within the earlier of the stated grace period or the next 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 28, 2023 | Prospectus   A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
i: This suffix was used for issues in which the credit factors, terms, or both that determine the likelihood of receipt of payment of interest are different from the credit factors, terms, or both that determine the likelihood of receipt of principal on the obligation. The 'i' suffix indicated that the rating addressed the interest portion of the obligation only. The 'i' suffix was always used in conjunction with the 'p' suffix, which addresses likelihood of receipt of principal. For example, a rated obligation could have been assigned a rating of 'AAApNRi' indicating that the principal portion was rated 'AAA' and the interest portion of the obligation was not rated.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary noncredit-related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met; however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Very low margin for safety. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.
A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.

April 28, 2023 | Prospectus   A-6

PIMCO Variable Insurance Trust

Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention (a long-term rating can also be used to rate an issue with short maturity). Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.
F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
SS&C Global Investor & Distribution Solutions, Inc., 430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary. Instead, the shareholder reports will be made available on a web site, and the insurance company will notify you by mail each time a report is posted and provide you with a web site link to access the report. Instructions for requesting paper copies will be provided by the insurance company. Paper copies of the Portfolio’s shareholder reports are required to be provided free of charge by the insurance company.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s web site at www.sec.gov . You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to [email protected]. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0593F_042823