Results of Operations

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 27, 2026 (April 21, 2026) PEOPLES BANCORP INC. (Exact name of Registrant as specified in its charter) Ohio 000-16772 31-0987416 (State or other jurisdiction (Commission File (I.R.S. Employer of incorporation) Number) Identification Number) 138 Putnam Street, PO Box 738 Marietta, Ohio 45750-0738 (Address of principal executive offices) (Zip Code) Registrant's telephone number, including area code: (740) 373-3155 Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: ☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act: Title of each class Trading Symbol(s) Name of each exchange on which registered Common shares, without par value PEBO The Nasdaq Stock Market Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ Item 2.02     Results of Operations and Financial Condition On April 21, 2026, management of Peoples Bancorp Inc. (“Peoples”) conducted a facilitated conference call at approximately 11:00 a.m., Eastern Standard Time, to discuss results of operations for the quarter and fiscal year ended March 31, 2026. A replay of the conference call audio will be available on Peoples’ website, www.peoplesbancorp.com, in the “Investor Relations” section for one year. A copy of the transcript of the conference call is included as Exhibit 99.1 to this Current Report on Form 8-K. The information contained in this Item 2.02 and Exhibit 99.1 included with this Current Report on Form 8-K, is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall such information be deemed to be incorporated by reference in any registration statement or other document filed under the Securities Act of 1933, as amended, or the Exchange Act, except as otherwise stated in such filing. During the conference call, management referred to non-Generally Accepted Accounting Principles ("US GAAP") financial measures that are used by management to provide information useful to investors in understanding Peoples' operating performance and trends, and to facilitate comparisons with the performance of Peoples' peers. The following tables show the differences between the non-US GAAP financial measures referred to during the conference call and the most directly comparable US GAAP-based financial measures. Three Months Ended March 31, December 31, March 31, (Dollars in thousands) 2026 2025 2025 Efficiency ratio: Total non-interest expense $ 71,635  $ 71,294  $ 70,787  Less: amortization of other intangible assets 1,697  2,210  2,213  Adjusted total non-interest expense 69,938  69,084  68,574  Total non-interest income 28,254  26,272  27,099  Less: net (loss) gain on investment securities —  (77) (2) Less: net loss on asset disposals and other transactions (410) (1,908) (361) Total non-interest income, excluding net gains and losses 28,664  28,257  27,462  Net interest income 90,420  91,049  85,255  Add: fully tax-equivalent adjustment (a) 245  266  283  Net interest income on a fully tax-equivalent basis 90,665  91,315  85,538  Adjusted revenue $ 119,329  $ 119,572  $ 113,000  Efficiency ratio 58.61  % 57.78  % 60.68  % (a) Tax effect is calculated using a 21% statutory federal corporate income tax rate. At or For the Three Months Ended March 31, December 31, September 30, June 30, March 31, (Dollars in thousands, except per share data) 2026 2025 2025 2025 2025 Tangible equity: Total stockholders' equity $ 1,216,040  $ 1,206,602  $ 1,182,776  $ 1,153,350  $ 1,137,821  Less: goodwill and other intangible assets 391,601  393,319  395,535  397,785  400,099  Tangible equity $ 824,439  $ 813,283  $ 787,241  $ 755,565  $ 737,722  Tangible assets: Total assets $ 9,648,087  $ 9,649,630  $ 9,623,944  $ 9,540,608  $ 9,246,000  Less: goodwill and other intangible assets 391,601  393,319  395,535  397,785  400,099  Tangible assets $ 9,256,486  $ 9,256,311  $ 9,228,409  $ 9,142,823  $ 8,845,901  Tangible book value per common share: Tangible equity $ 824,439  $ 813,283  $ 787,241  $ 755,565  $ 737,722  Common shares outstanding 35,925,945  35,714,484  35,705,369  35,673,721  35,669,100  Tangible book value per common share $ 22.95  $ 22.77  $ 22.05  $ 21.18  $ 20.68  Tangible equity to tangible assets ratio: Tangible equity $ 824,439  $ 813,283  $ 787,241  $ 755,565  $ 737,722  Tangible assets $ 9,256,486  $ 9,256,311  $ 9,228,409  $ 9,142,823  $ 8,845,901  Tangible equity to tangible assets 8.91  % 8.79  % 8.53  % 8.26  % 8.34  % Three Months Ended March 31, December 31, March 31, (Dollars in thousands) 2026 2025 2025 Pre-provision net revenue: Income before income taxes $ 37,345  $ 37,977  $ 31,377  Add: provision for credit losses 9,694  8,050  10,190  Add: net loss on OREO 26  851  —  Add: net loss on investment securities —  77  2  Add: net loss on other assets 384  210  330  Add: net loss on other transactions —  847  51  Pre-provision net revenue $ 47,449  $ 48,012  $ 41,930  Three Months Ended March 31, September 30, March 31, (Dollars in thousands) 2026 2026 2025 Annualized net income adjusted for non-core items: Net income $ 29,006  $ 31,754  $ 24,336  Add: net loss on investment securities —  77  2  Less: tax effect of net loss on investment securities (a) —  16  —  Add: net loss on asset disposals and other transactions 410  1,908  361  Less: tax effect of net loss on asset disposals and other transactions (a) 86  401  76  Net income adjusted for non-core items $ 29,330  $ 33,322  $ 24,623  Days in the period 90  92  90  Days in the year 365  365  365  Annualized net income $ 117,635  $ 125,981  $ 98,696  Annualized net income adjusted for non-core items $ 118,949  $ 132,201  $ 99,860  Return on average assets: Annualized net income $ 117,635  $ 125,981  $ 98,696  Total average assets $ 9,601,108  $ 9,630,774  $ 9,195,467  Return on average assets 1.23  % 1.31  % 1.07  % Return on average assets adjusted for non-core items: Annualized net income adjusted for non-core items $ 118,949  $ 132,201  $ 99,860  Total average assets $ 9,601,108  $ 9,630,774  $ 9,195,467  Return on average assets adjusted for non-core items 1.24  % 1.37  % 1.09  % (a) Tax effect is calculated using a 21% statutory federal corporate income tax rate. For the Three Months Ended March 31, September 30, March 31, (Dollars in thousands) 2026 2026 2025 Annualized net income excluding amortization of other intangible assets: Net income $ 29,006  $ 31,754  $ 24,336  Add: amortization of other intangible assets 1,697  2,210  2,213  Less: tax effect of amortization of other intangible assets (a) 356  464  465  Net income excluding amortization of other intangible assets $ 30,347  $ 33,500  $ 26,084  Days in the period 90  92  90  Days in the year 365  365  365  Annualized net income $ 117,635  $ 125,981  $ 98,696  Annualized net income excluding amortization of other intangible assets $ 123,074  $ 132,908  $ 105,785  Average tangible equity: Total average stockholders' equity $ 1,218,368  $ 1,196,505  $ 1,122,860  Less: average goodwill and other intangible assets 392,490  394,409  401,344  Average tangible equity $ 825,878  $ 802,096  $ 721,516  Return on average stockholders' equity ratio: Annualized net income $ 117,635  $ 125,981  $ 98,696  Average stockholders' equity $ 1,218,368  $ 1,196,505  $ 1,122,860  Return on average stockholders' equity 9.66  % 10.53  % 8.79  % Return on average tangible equity ratio: Annualized net income excluding amortization of other intangible assets $ 123,074  $ 132,908  $ 105,785  Average tangible equity $ 825,878  $ 802,096  $ 721,516  Return on average tangible equity 14.90  % 16.57  % 14.66  % (a) Tax effect is calculated using a 21% statutory federal corporate income tax rate. Item 9.01      Financial Statements and Exhibits a) - c) Not applicable d) Exhibits See Index to Exhibits below. INDEX TO EXHIBITS Exhibit Number Description 99.1 Transcript of conference call conducted by management of Peoples Bancorp Inc. on April 21, 2026 to discuss results of operations for the quarter ended March 31, 2026 104 Cover Page Interactive Data File (the cover page XBRL tags are embedded within the Inline XBRL document) SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. PEOPLES BANCORP INC. Date: April 27, 2026 By:/s/ KATHRYN BAILEY Kathryn Bailey Executive Vice President, Chief Financial Officer and Treasurer