Form 497K BAILLIE GIFFORD FUNDS

Baillie Gifford Positive Change Equities Fund

Before you invest, you may want to review the Fund's full prospectus, which contains more information about the Fund and its risks. You can find the Fund's full prospectus and other information about the Fund, including its statement of additional information ("SAI") and most recent reports to shareholders, online at http://USmutualfund.bailliegifford.com. You can also get this information at no cost by calling 1-844-394-6127 or by emailing [email protected]. This Summary Prospectus incorporates by reference the Fund's entire prospectus and SAI, each dated May 1, 2021, as supplemented or revised, and the financial statements included in the Fund's annual report to shareholders, dated December 31, 2020.

Investment Objective

Baillie Gifford Positive Change Equities Fund seeks capital appreciation with an emphasis on investing in businesses that deliver positive change by contributing towards a more sustainable and inclusive world.

Fees and Expenses

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

Shareholder Fees

(Fees paid directly from your investment)

Annual Fund Operating Expenses

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

^(a)  The Management Fee consists of an Advisory Fee and an Administration and Supervisory Fee paid by the Fund to Baillie Gifford Overseas Limited.

^(b)  Baillie Gifford Overseas Limited has contractually agreed to waive its fees and/or bear Other Expenses of the Fund until April 30, 2022 to the extent that such Fund's Total Annual Operating Expenses (excluding taxes, sub-accounting expenses and extraordinary expenses) exceed 0.65% for Class K and Institutional Class shares. This contractual agreement may only be terminated by the Board of Trustees of the Trust. Expenses after waiver/reimbursement exceed 0.65% for Institutional Class due to sub-accounting expenses of 0.03%.

Example of Expenses

The example below is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in the Fund for the time periods indicated, regardless of whether or not you redeem your shares at the end of such periods. It also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The example below also applies any contractual expense waivers and/or expense reimbursements to the first year of each period listed in the table.

Although your actual costs may be higher or lower, based on these assumptions, your expenses would be:

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These transaction costs, which are not reflected in "Annual Fund Operating Expenses" or in the "Example of Expenses" above, affect the Fund's performance. During the Fund's most recent fiscal year, the Fund's portfolio turnover rate was 40% of the average value of its portfolio.

Principal Investment Strategies

The Fund seeks to meet its objective by investing in a global portfolio of equities, which include common stock and other equity securities, of issuers located in countries of developed, emerging, and frontier markets. Under normal circumstances, the Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in equity securities. The Fund invests predominantly in securities issued by companies located in countries represented in the MSCI ACWI Index, cash and cash equivalents.

Baillie Gifford Positive Change Equities Fund – Summary Prospectus

The Fund invests in equity securities either directly or indirectly, such as through depositary receipts, and may invest in preferred stocks, convertible securities and warrants. The Fund is not constrained with respect to market capitalization and may participate in initial public offerings ("IPOs") and in securities offerings that are not registered in the U.S.

The portfolio managers employ a bottom-up approach to stock selection and select companies without being constrained by the MSCI ACWI benchmark. The portfolio managers focus on company research and the long-term outlook of companies and industries. Ideas can come from a wide variety of sources, including, but not limited to, research trips, company meetings, and relationships with industry thought leaders and academic institutions. Stock ideas are normally researched to assess a range of factors, including: long-term growth potential, geographic and industry positioning, competitive advantage, management, financial strength and valuation. The intended outcome is a portfolio of between 25 and 50 growth companies with the potential to outperform the benchmark over the long term and which the portfolio managers consider to have core ambitions of delivering a positive change in at least one of the following areas: social inclusion and education, healthcare, the environment, and addressing basic needs and aspirations of the world's poorest populations. In order to assess positive change in these areas, Baillie Gifford Overseas Limited (the "Manager") will monitor the progress of each issuer using metrics and/or milestones designed by the Manager. With respect to each area, the Manager pursues an active, positive approach; investment decisions are generally not made on the basis of negative "screening" of companies viewed as socially irresponsible. The process can result in significant exposure to a single country or a small number of countries, which in recent periods has included Japan.

The Fund is a non-diversified fund, which means that it may invest a relatively large percentage of its assets in a small number of issuers, industries or sectors. The Fund aims to hold securities for long periods (typically 5-10 years), which results in relatively low portfolio turnover and is in line with the Fund's long-term investment outlook.

The Fund may invest without limitation in securities quoted or denominated in currencies other than the U.S. dollar and may hold such currencies. The Fund does not expect to engage in currency hedging and thus expects to be fully exposed to currency fluctuations relative to the U.S. dollar.

Principal Risks

The Fund's net asset value and returns will be impacted by the performance of the underlying investments of the Fund. An investment in the Fund is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the Fund.

The principal risks of investing in the Fund (in alphabetical order after the first five risks) are:

—  Investment Style Risk – The Manager actively makes investment decisions for the Fund through bottom-up stock selection. Accordingly, the Fund will have risk characteristics that differ from its benchmark index. The Manager's

judgments about the attractiveness, relative value, or potential appreciation of a particular stock may prove to be incorrect and cause the Fund to lose money or underperform compared to its benchmark index. There can be no assurance that the Manager's investment decisions will produce the desired results.

—  Growth Stock Risk – The prices of growth stocks may be based largely on expectations of future earnings, and their prices can decline rapidly and significantly in reaction to negative news. Growth stocks may underperform stocks in other broad style categories (and the stock market as a whole) over any period of time and may shift in and out of favor with investors generally, sometimes rapidly, depending on changes in market, economic, and other factors.

—  Long-Term Investment Strategy Risk – The Fund pursues a long-term investment approach, typically seeking returns over a period of several years. This investment style may cause the Fund to lose money or underperform compared to its benchmark index or other mutual funds over extended periods of time, and the Fund may not perform as expected in the long term. An investment in the Fund may be more suitable for long-term investors who can bear the risk of short- or medium-term fluctuations in the value of the Fund's portfolio.

—  Non-Diversification Risk – The Fund is classified as a "non-diversified" fund. Because the Fund may invest a relatively large percentage of its assets in a single issuer or small number of issuers, its performance could be closely tied to the value of that one issuer or those few issuers, and could be more volatile than the performance of diversified funds.

—  Impact Risk – A Fund may not be successful in assessing and identifying companies that have or will have a positive impact or support a given position. In some circumstances, companies could ultimately have a negative impact, or no impact, on addressing a global challenge, or on environmental, social and/or governance matters. See also "Socially Responsible Investing Risk."

—  Asia Risk – Investing in securities of companies located in or with exposure to Asian countries involves certain risks and considerations not typically associated with investing in securities of U.S. issuers, including different financial reporting standards, currency exchange rate fluctuations, and highly regulated markets with the potential for government interference. The economies of many Asian countries are heavily dependent on international trade and on only a few industries or commodities and, as a result, can be adversely affected by trade barriers, exchange controls and other measures imposed or negotiated by the countries with which they trade. Some Asian securities may be less liquid than U.S. or other foreign securities. See "Japan Risk" for additional details regarding the risks of investing in that country.

  Additionally, many of the economies of countries in Asia are considered emerging market or frontier market economies. These Asian economies are often characterized by high inflation, undeveloped financial service sectors, frequent currency fluctuations, devaluations, or restrictions, political and social instability, and less efficient markets. See

Baillie Gifford Positive Change Equities Fund – Summary Prospectus

"Emerging Markets Risk" and "Frontier Markets Risk" for additional details regarding the risks of investing in such countries.

—  Conflicts of Interest Risk – The Manager's relationships with the Fund's institutional investor base may give rise to various conflicts of interest, since the Manager will sometimes have an incentive to favor those shareholders over other shareholders in the Fund. In addition, the Manager serves as investment adviser to various clients other than the Fund, some of whom may pursue strategies that are substantially similar or nearly identical to investment strategies pursued by the Fund. This "side-by-side" management may give rise to various conflicts of interest, including, for example, in connection with the fair allocation of trades among the Manager's clients or the sharing of different, more, or more timely information regarding investment performance, portfolio holdings, strategy developments and/or the Manager's general market outlook. Furthermore, if investment personnel of the Manager hold board or other positions at outside companies, they could be exposed to material non-public information potentially impeding or delaying a Fund's ability to buy or sell certain investments, or they could otherwise be restricted in their ability to participate in a Fund's investment process.

—  Currency Risk – The Fund may realize a loss if it has exposure to a non-U.S. currency, and this non-U.S. currency declines in value, relative to the U.S. dollar. The Fund does not expect to engage in currency hedging and thus expects to be fully exposed to currency fluctuations relative to the U.S. dollar.

—  Emerging Markets Risk – To the extent the Fund invests in emerging market securities, the Fund may be exposed to greater market, credit, currency, liquidity, legal, political, technical and other risks different from, or greater than, the risks of investing in developed markets.

—  Equity Securities Risk – Equity securities may react more strongly to changes in an issuer's financial condition or prospects than other securities of the same issuer. Investing in equity securities indirectly, such as through participatory notes or depositary receipts, may involve other risks such as the risk that the counterparty may default or that the investment does not track the underlying security as expected.

—  Focused Investment Risk – Because the Fund focuses its investments in a limited number of companies, its investment strategy could result in more risk or greater volatility in returns than if the Fund's investments were less focused.

—  Frontier Markets Risk – Frontier markets are those emerging markets that are considered to be among the smallest, least mature and least liquid and, as a result, may be more volatile and less liquid than investments in more developed markets or in other emerging market countries. Emerging markets risk may be especially heightened in frontier markets.

—  Government and Regulatory Risk – Governmental and regulatory authorities in the United States and other countries, have taken, and may in the future take, actions intervening in the markets in which the Fund invests and in

the economy more generally. Governmental and regulatory authorities may also act to increase the scope or burden of regulations applicable to the Fund or to the companies in which the Fund invests. The effects of these actions on the markets generally, and Fund's investment program in particular, can be uncertain and could restrict the ability of the Fund to fully implement its investment strategies, either generally, or with respect to certain securities, industries, or countries. By contrast, markets in some non-U.S. countries historically have been subject to little regulation or oversight by governmental or regulatory authorities, which could heighten the risk of loss due to fraud or market failures in those countries. Governments, agencies, or other regulatory bodies in any country may adopt or change laws or regulations that could adversely affect the Fund or the market value of an instrument held by the Fund.

—  Information Technology Risk – Cyber-attacks, disruptions, or failures that affect the Fund's service providers, counterparties, the securities markets generally, other market participants, or issuers of securities held by the Fund may adversely affect the Fund and its shareholders, including by causing losses for the Fund or impairing Fund operations.

—  IPO Risk – The Fund may purchase securities in IPOs. These securities are subject to many of the same risks of investing in companies with smaller market capitalizations. Securities issued in IPOs have no trading history, and information about the companies may be available for very limited periods. In addition, the prices of securities sold in IPOs may be highly volatile.

—  Japan Risk – The Japanese economy has only recently emerged from a prolonged economic downturn. Since the year 2000, Japan's economic growth rate has remained relatively low, and it may remain low in the future. Japan's economy is characterized by an aging demographic, declining population, large government debt, and a highly regulated labor market. In the longer term, Japan will have to address the effects of an aging population, including the impact of a shrinking work force and higher welfare costs. Japan's economic recovery has been affected by economic distress resulting from a number of natural disasters, including disasters that caused damage to nuclear power plants in the region. Such environmental catastrophes have caused Japan's financial markets to fluctuate dramatically. Japan continues to be subject to the risk of natural disasters, such as earthquakes, volcanic eruptions, typhoons and tsunamis, which could negatively affect the Japanese economy.

—  Large-Capitalization Securities Risk – Returns on investments in securities of large companies could trail the returns on investments in securities of smaller and medium-sized companies. Larger companies may be unable to respond as quickly as smaller and medium-sized companies to competitive challenges or to changes in business, product, financial, or other market conditions. Larger companies may not be able to achieve or maintain growth at the high rates that may be achieved by well-managed smaller and medium-sized companies.

Baillie Gifford Positive Change Equities Fund – Summary Prospectus

—  Liquidity Risk – The Fund's investments may be subject to low trading volume, lack of a market maker, contractual lock-in periods or regulatory restrictions, and the Fund may hold large positions in particular securities. As a result, it may not be possible to sell an investment at a particular time or at an acceptable price. Liquidity risk may be magnified during periods of changing interest rates, significant shareholder redemptions or market turmoil. Illiquid securities may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. In some cases, due to unanticipated levels of illiquidity the Fund may seek to meet its redemption obligations wholly or in part by distributions of assets in-kind.

—  Market Disruption and Geopolitical Risk – The value of the Fund's investments could be adversely affected by events that disrupt securities markets and adversely affect global markets such as war, terrorism, public health crises, and geopolitical events and by changes in non-U.S. and U.S. economic and political conditions. As a result of these events, the Fund could lose money, experience significant redemptions, encounter operational difficulties, and suffer other negative impacts.

—  Market Risk – The value of the Fund's investments will be affected by fluctuations in the stock markets in which the Fund is invested, factors affecting a particular industry or industries, real or perceived adverse economic conditions, changes in interest or currency rates or adverse investor sentiment generally. Declines in securities market prices may reduce the net asset value of the Fund's shares.

—  Non-U.S. Investment Risk – Non-U.S. securities are subject to additional risks, including less liquidity, increased volatility, less transparency, withholding or other taxes, increased vulnerability to adverse changes in local and global economic conditions, less regulation, and possible fluctuation in value due to adverse political conditions. Foreign portfolio transactions generally involve higher commission rates, transfer taxes, and custodial costs than similar transactions in the U.S.

—  Service Provider Risk – The Fund will be affected by the Manager's investment techniques, analyses, assessments and employee retention. Similarly, adverse events or performance failures at a service provider, such as human error, inadequate controls or insolvency, have the ability to adversely affect the Fund.

—  Settlement Risk – The Fund may experience delays in settlement due to the different clearance and settlement procedures in non-U.S. countries. Such delays may increase credit risk to the Fund, limit the ability of the Fund to reinvest the proceeds of a sale of securities, or prevent the Fund from selling securities at times and prices it considers desirable.

—  Small-and Medium-Capitalization Securities Risk – Securities of small- and medium-capitalization companies can be more volatile due to various factors including more limited product lines, financial and management resources and market distribution channels, as well as shorter operating histories and potentially reduced liquidity, especially during market declines, than the securities of larger, more established companies.

—  Socially Responsible Investing Risk – The Fund's incorporation of environmental, social and/or governance considerations in its investment process may cause it to make different investments than funds that have a similar investment universe and/or investment style but that do not incorporate such considerations in their strategy or investment processes. As a result, such Fund may forego opportunities to buy certain securities when it might otherwise be advantageous to do so, or sell securities when it might be otherwise disadvantageous for it to do so. See also "Impact Risk."

—  Valuation Risk – In certain circumstances, some of the Fund's portfolio holdings may be valued on the basis of factors other than market quotations by employing the fair value procedures adopted by the Board of Trustees of the Trust (the "Board"). This may occur more often in times of market turmoil or reduced liquidity. Portfolio holdings that are valued using techniques other than market quotations, including "fair valued" securities, may be subject to greater fluctuation in their valuations from one day to the next than if market quotations were used. There is no assurance that the Fund could sell or close out a portfolio position for the value established for it at any time, and it is possible that the Fund would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by the Fund at that time.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's annual total returns from year to year and by comparing the Fund's average annual total returns with those of the Fund's benchmark. Past performance (before and after taxes) is not an indication of future performance.

Annual Total Returns — Institutional Class Shares

In the table below, after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. After-tax returns are shown for Institutional Class shares only, and after-tax returns for other share classes will vary. Actual after-tax returns depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant if you are tax-exempt or if you hold your Fund shares through tax-advantaged arrangements. A description of the Fund's comparative index and

Baillie Gifford Positive Change Equities Fund – Summary Prospectus

details regarding the calculation of the Fund's class-by-class performance are provided in the section of the Prospectus entitled "Additional Performance Information."

⁽¹⁾  The source of the index data is MSCI Inc. MSCI makes no express or implied warranties or representations and shall have no liability whatsoever with respect to any MSCI data contained herein. The MSCI data may not be further redistributed or used as a basis for other indexes or any securities or financial products. This Prospectus is not approved, endorsed, reviewed or produced by MSCI. None of the MSCI data is intended to constitute investment advice or a recommendation to make (or refrain from making) any kind of investment decision and may not be relied on as such.

Updated information on the Fund's investment performance can be obtained by visiting http://USmutualfund.bailliegifford.com.

Management

Investment Manager

Baillie Gifford Overseas Limited

Portfolio Managers

Purchasing, Exchanging, and Selling Fund Shares

To purchase, exchange, or redeem shares of the Fund through an intermediary, please contact your intermediary directly.

Other investors may purchase, exchange, or redeem shares on any day the New York Stock Exchange ("NYSE") is open for trading directly from the Fund's transfer agent, Bank of New York Mellon, by written request, as further described in the sections of the Prospectus entitled "Shares—How to Buy or Exchange Shares" and "Shares—How to Sell Shares." The initial and subsequent investment minimums for the Fund shares are as follows:

⁽¹⁾  If you hold shares through a financial intermediary, the financial intermediary may impose its own, different, investment minimums.

The Manager and Baillie Gifford Funds Services LLC ("BGFS"), the Fund's distributor, each reserves the right to waive any minimum in their sole discretion, and to reject any purchase or exchange order for any reason. Additional information regarding restrictions on purchasing or exchanging shares is provided in the section of the Prospectus entitled "Shares—Restrictions on Buying or Exchanging Shares."

Tax

The Fund intends to make distributions that will be taxable to you as ordinary income or capital gains, unless you are a tax-exempt investor or otherwise investing through a tax-advantaged account, such as an IRA or 401(k) plan. If you are investing through such a tax-advantaged account, you may be taxed later upon withdrawal of monies from that account.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase Fund shares through a broker-dealer or other financial intermediary, the Fund and its related companies may pay the intermediary for services the intermediary provides to Fund shareholders. These payments are not primarily intended to result in the sale of Fund shares. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. In addition to the fees and expenses described in the "Fees and Expenses" section above, your broker-dealer or financial intermediary may charge commissions or other fees on purchases and sales of the Class K or Institutional Class shares of the Fund. Ask your salesperson or visit your financial intermediary's web site for more information.