Harris Associates Investment Trust Oakmark Fund Oakmark Bond Fund Supplement dated April 30, 2021 to each Fund’s Prospectus, Summary Prospectus, and Statement of Additional Information, each dated December 15, 2020 Kevin G. Grant, portfolio manager of Oakmark Fund (the “Fund”) and Co-Chairman and analyst of the Adviser, has announced his decision to retire from his roles effective December 31, 2021. Mr. Grant will cease his portfolio management and advisory responsibilities and all references to Mr. Grant will be removed in the Oakmark Fund’s Summary Prospectus, Prospectus and Statement of Additional Information at that time. After Mr. Grant’s retirement, William C. Nygren and Michael A. Nicolas will continue as portfolio managers of the Oakmark Fund. Effective on May 1, 2021: (1) The fee table and expense example included in the Oakmark Bond Fund’s Summary Prospectus and Prospectus are hereby deleted and replaced with the following: Advisor Institutional R6 Class Class Class Management fees 0.39% 0.39% 0.39% Distribution (12b-1) fees None None None Other expenses(1) 1.91% 2.43% 2.43% Total Annual Fund Operating Expenses 2.30% 2.82% 2.82% Less: Fee waivers and/or Expense reimbursements 1.76% 2.30% 2.38% Total Annual Fund Operating Expenses after fee waivers and/or expense reimbursements(2) 0.54% 0.52% 0.44% (1) "Other expenses" are based on estimated amounts for the current fiscal year; actual expenses may vary. (2) Harris Associates L.P. (the "Adviser") has contractually undertaken to waive and/or reimburse certain fees and expenses of Advisor Class, Institutional Class, and R6 Class so that the total annual operating expenses (excluding taxes, interest, all commissions and other normal charges incident to the purchase and sale of portfolio securities, and extraordinary charges such as litigation costs, but including fees paid to the Adviser) ("annual operating expenses") of each class are limited to 0.54%, 0.52%, and 0.44% of average net assets, respectively. Each of these undertakings lasts until 1/27/2022 and may only be modified by mutual agreement of the parties that, with respect to the Trust, includes a majority vote of the "non-interested" Trustees of the Trust. The Fund has agreed that each of Advisor Class, Institutional Class, and R6 Class will repay the Adviser for fees and expenses waived or reimbursed for the class provided that repayment does not cause annual operating expenses to exceed 0.54%, 0.52%, and 0.44% of the class' average net assets, respectively, or to exceed any lower limit in effect at the time of recoupment. Any such repayment must be made within three years after the year in which the Adviser incurred the expense. Example. The Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses were those reflected in the table, inclusive of any fee waivers and/or expense reimbursements. Although your actual returns and expenses may be higher or lower, based on these assumptions your expenses would be: Advisor Institutional R6 Class Class Class 1 Year $ 55 $ 53 $ 45 3 Years 549 655 648 (2) The table that appears on page 94 of the Prospectus is hereby deleted and replaced with the following: The Adviser has contractually agreed to reimburse each Fund Class to the extent that its annual ordinary operating expenses of a class exceed the following percentages of the average daily net assets of that class: Investor Advisor Institutional R6 Service Fund* Class Class Class Class Class Oakmark Fund 1.40% 1.15% 1.10% 0.95% 1.40% Select Fund 1.50 1.25 1.20 1.05 1.50 Global Fund 1.55 1.30 1.25 1.10 1.55 Global Select Fund 1.55 1.30 1.25 1.10 N/A International Fund 1.55 1.30 1.25 1.10 1.55 International Small Cap Fund 1.75 1.50 1.45 1.30 1.75 Equity and Income Fund 1.25 1.00 0.95 0.80 1.25 Bond Fund N/A 0.54 0.52 0.44 N/A * The agreement for each Fund is effective through January 27, 2022. The Adviser is entitled to recoup from assets attributable to any Fund class amounts reimbursed to that Fund class, except to the extent that the Fund class already has paid such recoupment to the Adviser or such recoupment would cause the annual ordinary operating expenses of a Fund class for that fiscal year to exceed the applicable limit shown above or to exceed any lower limit in effect at the time of recoupment. Any such repayment must be made within three years after the year in which the reimbursement occurred. (2) The first paragraph in the “Expense Limitation Agreement” section of the Statement of Additional Information is hereby deleted in its entirety and replaced with the following: Bond Fund Only. The Adviser has contractually agreed, through January 27, 2022, to reimburse each class of the Bond Fund to the extent that the annual ordinary operating expenses of that class exceed the following percentages of average net assets: 0.54% in the case of Advisor Class Shares; 0.52% in the case of Institutional Class Shares; and 0.44% in the case of R6 Class Shares. PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE. Toppan Merrill - Harris-Oakmark Harris Associates Investment Trust Bond 497K 033-38953 12-15-2020 ED | saries | 15-Dec-20 14:58 | 20-37474-11.ba | Sequence: 1 CHKSUM Content: 53180 Layout: 1139 Graphics: 49166 CLEAN Click to view the Fund’s Prospectus or Statement of Additional Information CXPRO2890 Summary Prospectus December 15, 2020 OAKMARK BOND FUND Advisor Class Institutional Class R6 Class OAYCX OANCX OAZCX Beginning on January 1, 2021, as permitted by regulations adopted by the U.S. Securities and Exchange Commission, paper copies of the Oakmark Funds’ annual and semi-annual shareholder reports will no longer be sent by mail, unless you specifically request paper copies of the reports. Instead, the reports will be made available on Oakmark.com, and you will be notified by mail each time a report is posted and provided with a website link to access the report. If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the Funds electronically anytime by contacting your financial intermediary (such as a broker-dealer or bank) or, if you hold your shares directly with the Funds, by calling 1-800-OAKMARK (625-6275) or visiting Oakmark.com. You may elect to receive all future reports in paper free of charge. If you invest through a financial intermediary, you can contact your financial intermediary to request that you continue to receive paper copies of your shareholder reports. If you hold your shares directly with the Funds, you can call 1-800-OAKMARK (625-6275) to let the Funds know you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all Funds you hold directly or all Funds you hold through your financial intermediary, as applicable. Before you invest, you may want to review the Fund’s prospectus and statement of additional information, which contain more information about the Fund and its risks. You can find the Fund’s prospectus and other information about the Fund online at www.Oakmark.com/prospectus. You can also get this information at no cost by calling 1-800-OAKMARK or by sending an email request to [email protected]. The Fund’s prospectus and statement of additional information, dated January 28, 2020, and as each may be further supplemented or amended, are incorporated by reference into this Summary Prospectus. INVESTMENT OBJECTIVE assets, respectively, or to exceed any lower limit in effect at the time of recoupment. Any such repayment must be made within three years after The Fund seeks to maximize both current income and total the year in which the Adviser incurred the expense. return, consistent with prudent investment and principal protection management. Example. The Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other FEES AND EXPENSES OF THE FUND mutual funds. The Example assumes that you invest $10,000 for Below are the fees and expenses that you would pay if you buy the time periods indicated and then redeem all of your shares at and hold shares of the Fund. the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s Shareholder Fees (fees paid directly from your investment) operating expenses were those reflected in the table, inclusive of None. any fee waivers and/or expense reimbursements. Although your actual returns and expenses may be higher or Annual Fund Operating Expenses (expenses that you pay each lower, based on these assumptions your expenses would be: year as a percentage of the value of your investment). Advisor Institutional R6 Advisor Institutional R6 Class Class Class Class Class Class 1 Year $ 65 $ 60 $ 45 Management fees 0.39% 0.39% 0.39% 3 Years 559 662 648 Distribution (12b-1) fees None None None Other expenses1 1.91% 2.43% 2.43% Portfolio Turnover Total Annual Fund Operating The Fund pays transaction costs, such as commissions, when it Expenses 2.30% 2.82% 2.82% buys and sells securities (or “turns over” its portfolio).