Summary Prospectus by Investment Company - Form 497K

Annual Fund Operating Expenses

(expenses that you pay each year as a percentage of the value of your investment)

Management Fees⁽¹⁾

Distribution and Service (12b-1) Fees

Other Expenses⁽²⁾

Total Annual Fund Operating Expenses

Less Waivers⁽¹⁾

Net Annual Fund Operating Expenses

Olive Street Investment Advisers, LLC (the "Adviser") has contractually agreed, until at least October 28, 2025, to waive its management fees to the extent management fees to be paid to the Adviser exceed the management fees the Fund is required to pay the Fund's sub-advisers (i.e., the Adviser does not receive any management fees from the Fund as a result of its waivers). This contractual agreement may not be terminated by the Adviser without the consent of the Board of Trustees (the "Board") of Bridge Builder Trust (the "Trust"), except that the Adviser may terminate the agreement upon written notice to the Trust, effective as of the end of the expense limitation period ending October 28, 2025, if written notice is provided to the Trust by or before a date agreed to by the Board. Such waivers are not subject to reimbursement by the Fund.

Other Expenses include acquired fund fees and expenses less than 0.01%.

Market Risk. The overall market may perform poorly or the returns from the securities in which the Fund invests may underperform returns from the general securities markets, a particular securities market, or other types of investments. A variety of factors can influence underperformance and can have a significant impact on the Fund and its investments, including regulatory events, inflation, interest rates, government defaults, government shutdowns, war, regional conflicts, acts of terrorism, social unrest, and substantial economic downturn or recessions. In addition, the impact of any epidemic, pandemic, natural disaster, spread of infectious illness or other public health issue, or widespread fear that such events may occur, could negatively affect the global economy, as well as the economies of individual countries, the financial performance of individual companies and sectors, and the markets in general in significant and unforeseen ways. Any such impact could adversely affect the prices and liquidity of the securities and other instruments in which the Fund invests, which in turn could negatively impact the Fund's performance and cause losses on your investment in the Fund.

Interest Rate Risk. The value of fixed income securities may decline because of increases in interest rates or rise because of decreases in interest rates. The value of a fixed income security with greater duration will be more sensitive to changes in interest rates than a similar security with shorter duration. The prices of fixed income securities with shorter duration generally will be less affected by changes in interest rates than the prices of fixed income securities with greater duration. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly. Fluctuations in interest rates may also affect the liquidity of the fixed-income securities held by the Fund. As a result, it is possible that the Fund would, during these conditions, maintain a substantial portion of its assets in cash, on which it may earn little, if any, income. Changes in monetary policy made by central banks and/or their governments or changes in economic conditions may affect the level of interest rates, which could have sudden or unpredictable effects on the markets. A sudden or unpredictable rise or decline in interest rates may cause volatility and reduced liquidity in the markets, which could make it more difficult for the Fund to sell its investments at a time when it may be advantageous to do so and could cause the value of the Fund's investments to decline, potentially suddenly and significantly.

Credit Risk. Credit risk is the risk that the issuer of a bond will fail to make payments when due or default completely. If the issuer of the bond experiences an actual or anticipated deterioration in credit quality, the price of the bond may be negatively impacted. The degree of credit risk depends on the financial condition of the issuer and the terms of the bond.

Municipal Securities Risk. The value of the Fund's investments in municipal securities may be adversely affected by unfavorable legislative or political developments and economic developments that impact the financial condition of municipal issuers. For example, a credit rating downgrade, bond default, or bankruptcy involving an issuer within a particular state or territory could affect the market values and marketability of many or all

municipal obligations of that state or territory. Additionally, the relative amount of publicly available information about the financial condition of municipal securities issuers is generally less than that for corporate securities.

Active Management Risk. The Fund is actively managed with discretion and may underperform market indices, including relevant benchmark indices, or other mutual funds with similar investment objectives. In addition, to the extent that a Sub-adviser's investment strategy uses a quantitative investment model to evaluate and recommend investment decisions for the Fund, the Fund can perform differently from the market as a whole based on the factors used in the model, the weight placed on each factor and changes from the factors' historical trends.

Counterparty Risk. When the Fund enters into an investment contract, such as a derivative or a repurchase agreement, the Fund is exposed to the risk that the other party may be unable or unwilling to fulfill its obligations, which could adversely impact the value of the Fund.

Derivatives Risk. An investment in derivatives (such as futures contracts) may not perform as anticipated by the Sub-advisers, may not be able to be closed out at a favorable time or price, or may increase the Fund's volatility. Derivatives may create investment leverage so that when a derivative is used as a substitute for or alternative to a direct cash investment, the transaction may not provide a return that corresponds precisely with that of the cash investment, or when used for hedging purposes, the derivative may not provide the anticipated protection, causing the Fund to lose money on both the derivative and the exposure the Fund sought to hedge. Increases and decreases in the value of the Fund's portfolio may be magnified when the Fund uses leverage. Derivatives are also subject to correlation risk, which is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of derivatives is also subject to market risk, which is described above, and liquidity risk, which is described below.

High Yield Securities Risk. High yield, or "junk," securities involve greater risks of default or downgrade and are more volatile than investment grade securities because the prospect for repayment of principal and interest of these securities is speculative. High-yield securities also may be less liquid than higher quality investments. These securities may offer higher returns, but there is no guarantee that an investment in these securities will result in a high rate of return.

Investment Company and Exchange-Traded Fund Risk. An investment company, including an ETF, in which the Fund invests may not achieve its investment objective or execute its investment strategies effectively. Large purchase or redemption activity by shareholders of such an investment company might negatively affect the value of the investment company's shares. The Fund must also pay its pro rata portion of an investment company's fees and expenses.

Investment Strategy Risk. There is no assurance the Fund's investment objective will be achieved. Investment decisions may not produce the expected results. The value of the Fund may decline, and the Fund may underperform other funds with similar objectives or strategies.

Issuer-Specific Risk. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole or other similar securities.

Liquidity Risk. Low trading volume, a lack of a market maker, or contractual or legal restrictions may limit the Fund's ability to value securities or prevent the Fund from selling securities or closing derivative positions at desirable times or prices.

Multi-Manager and Multi-Style Management Risk. The Fund allocates its assets to multiple Sub-advisers believed to have complementary styles. These investment styles, at times, may not be complementary and could result in more exposure to certain types of securities. Because portions of the Fund's assets are managed by different Sub-advisers using different styles, the Fund could engage in overlapping or conflicting securities transactions. Overlapping transactions could lead to multiple Sub- advisers purchasing the same or similar securities at the same time, potentially leading to the Fund holding a more concentrated position in these securities. Conversely, certain Sub-advisers may be purchasing securities at the same time other Sub-advisers may be selling those same securities, which may lead to higher transaction expenses compared to a fund using a single investment management style.

Municipal Revenue Bond Risk. Municipal revenue bonds are used to finance municipal projects that generate revenue. These types of bonds may be more sensitive to adverse economic, business or political developments

than other types of municipal bonds. In addition, if the specified revenues from a project do not materialize, there is a risk that the bonds may not be repaid. As a result, the municipal revenue bonds in which the Fund invests may entail greater credit risk than the Fund's investments in other types of municipal bonds. Moreover, a change that affects one project, such as proposed legislation on the financing of the project, a shortage of the materials needed for the project, or a declining need for the project, would likely affect all similar projects, thereby increasing the Fund's market risk.

Prepayment and Extension Risk. When interest rates fall, issuers of high interest debt obligations, as well as issuers of callable bonds, may pay off the debts earlier than expected (prepayment risk), and the Fund may have to reinvest the proceeds at lower yields. When interest rates rise, issuers of lower interest debt obligations may pay off the debts later than expected (extension risk), thus keeping the Fund's assets tied up in lower interest debt obligations.

Private Activity Bonds Risk. Municipalities and other public authorities issue private activity bonds to finance development of industrial facilities for use by a private enterprise. The private enterprise pays the principal and interest on the bond and the issuing authority does not pledge its full faith, credit, and taxing power for repayment. The private enterprise can have a substantially different credit profile than the municipality or public authority. The Fund's investments in private activity bonds may subject certain shareholders to the Federal AMT.

Privately Issued Securities Risk. Investments in privately issued securities (e.g., Rule 144A securities) may be less liquid than in publicly traded securities. Although these securities may be resold in privately negotiated transactions, the prices realized from these sales could be less than those originally paid by the Fund or less than what may be considered the fair value of such securities. Furthermore, companies with securities that are not publicly traded are not subject to the disclosure and other investor protection requirements that might be applicable if the securities were publicly traded.

Redemption Risk. The Fund may experience losses or realize taxable gains when selling securities to meet redemption requests. This risk is greater for larger redemption requests or redemption requests during adverse market conditions. Large redemptions of the Fund's shares may force the Fund to sell securities at times when it would not otherwise do so and may cause the Fund's portfolio turnover rate and transaction costs to rise, which may negatively affect the Fund's performance and have adverse tax consequences for Fund shareholders.

Regulatory and Judicial Risk. The regulation of security markets, transactions and portfolio companies is subject to change. Such regulatory changes and judicial actions could have a substantial adverse effect on the Fund's performance.

Reinvestment Risk. Cash flows from fixed income securities are generally reinvested at current market rates. A decline in market rates may result in less attractive reinvestment opportunities and affect the Fund's ability to meet its investment objective.

Tax and Federal AMT Risk. The Fund will rely on the opinion of issuers' bond counsel and, in the case of derivative securities, sponsors' counsel, on the tax-exempt status of interest on municipal bond obligations and payments under tax-exempt derivative securities. Neither the Fund nor its Adviser or Sub-advisers will independently review the bases for those tax opinions, which may ultimately be determined to be incorrect and subject the Fund and its shareholders to substantial tax liabilities. Certain shareholders subject to the Federal AMT may be required to report the Fund's exempt interest distributions in determining their Federal AMT. Exempt-interest dividends may affect the federal corporate alternative minimum tax for certain corporations. The Fund may also not be a suitable investment for individual retirement accounts and other tax-deferred arrangements.

U.S. Government Securities Risk. U.S. government obligations are affected by changes or expected changes in interest rates, among other things. While U.S. Treasury obligations are backed by the full faith and credit of the U.S. government, such obligations are still subject to credit risk. Securities issued or guaranteed by federal agencies or authorities or U.S. government sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. government. Moreover, some securities are neither insured nor guaranteed by the U.S. government. The U.S. Department of the Treasury has the authority to provide financial support to certain of these debt obligations, but no assurance can be given that the U.S. government will do so. From time to time, uncertainty regarding the status of negotiations in the U.S. government to increase the statutory debt ceiling and/or failure to increase the statutory debt ceiling could increase the risk that the U.S. government may default on payments on certain U.S. government securities (including those held by the Fund), which could have a material adverse impact on the Fund.

Valuation Risk. Certain investments held by the Fund are generally valued using evaluated prices provided by third-party independent pricing services or, in some cases, using evaluated prices provided by dealers or the Adviser's valuation committee using fair valuation methodologies. The evaluated prices used by the Fund may be different from the evaluated prices or fair value used by other mutual funds or from the evaluated prices at which certain Fund's investments are actually bought and sold. The evaluated prices and fair value of certain Fund's investments may be subject to frequent and significant change and will vary depending on the information that is available to the pricing services providing the evaluated prices and the Adviser when it determines the fair value of the investments.

When-Issued, Delayed Delivery, and Forward Commitment Transactions Risk. 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. Therefore, these transactions may result in a form of leverage and increase the Fund's overall investment exposure. When the Fund has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Fund does not participate in future gains or losses with respect to the security. These transactions are also subject to counterparty risk, which is described above.

Zero Coupon Bonds Risk. The value of zero coupon bonds is subject to greater fluctuation in response to changes in market interest rates than the value of bonds which make regular payments of interest. Even though zero coupon bonds do not pay current interest in cash, the Fund is required to accrue interest income on such investments and may be required to distribute that income at least annually to shareholders. Thus, the Fund could be required at times to liquidate other investments in order to satisfy its dividend requirements.

Quarterly Returns

Highest (quarter ended December 31, 2023)

Lowest (quarter ended March 31, 2022)

Return Before Taxes

Return After Taxes on Distributions

Return After Taxes on Distributions and Sale of Fund Shares

Bloomberg Municipal Bond Index (reflects no deductions for fees, expenses or taxes)¹

Bloomberg Municipal 1-15 Year Index (reflects no deduction for fees, expenses or taxes)¹

Pursuant to new regulatory requirements, the Fund's broad-based securities market index has changed from the Bloomberg Municipal 1-15 Year Index to the Bloomberg Municipal Bond Index. The Bloomberg Municipal Bond Index is an unmanaged broad-based total return index composed of approximately 40,000 investment grade, fixed rate and tax-exempt issues, with a remaining maturity of at least one year. The Bloomberg Municipal 1-15 Year Index is a subset of the Bloomberg Municipal Bond Index covering only maturities between 1 and 17 years. The Bloomberg Municipal Bond Index is an unmanaged index composed of tax-exempt bonds with maturities greater than one year and a minimum credit rating of Baa. Index returns reflect the change in value, principal payments and interest of bonds in the index. The Fund's portfolio holdings may differ significantly from the securities held in the relevant index and, unlike a mutual fund, the performance of an unmanaged index does not reflect deductions for transaction costs, taxes, management fees or other expenses. You cannot invest directly in an index.

Baird

Senior Vice President and Portfolio Manager

Senior Vice President and Portfolio Manager

Senior Vice President and Portfolio Manager

BlackRock

Managing Director

Director

Director

FIAM

Portfolio Manager

Portfolio Manager

Portfolio Manager

MacKay Shields

Senior Portfolio Manager and Executive Managing Director

Senior Portfolio Manager and Managing Director

Portfolio Manager, Trader and Managing Director

Portfolio Manager, Trader and Director