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): October 27, 2025 (October 21, 2025) 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 October 21, 2025, 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 ended September 30, 2025. 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 Nine Months Ended September 30, June 30, September 30, September 30, (Dollars in thousands) 2025 2025 2024 2025 2024 Efficiency ratio: Total non-interest expense $ 69,894  $ 70,362  $ 66,090  $ 211,043  $ 203,313  Less: amortization of other intangible assets 2,211  2,211  2,786  6,635  8,361  Adjusted total non-interest expense 67,683  68,151  63,304  204,408  194,952  Total non-interest income 23,827  26,880  24,794  77,806  74,277  Less: net loss on investment securities (2,580) —  (74) (2,582) (428) Less: net loss on asset disposals and other transactions (478) (280) (795) (1,119) (1,564) Total non-interest income, excluding net gains and losses 26,885  27,160  25,663  81,507  76,269  Net interest income 91,349  87,577  88,912  264,181  262,165  Add: fully tax-equivalent adjustment (a) 279  280  318  842  1,022  Net interest income on a fully tax-equivalent basis 91,628  87,857  89,230  265,023  263,187  Adjusted revenue $ 118,513  $ 115,017  $ 114,893  $ 346,530  $ 339,456  Efficiency ratio 57.11  % 59.25  % 55.10  % 58.99  % 57.43  % (a) Tax effect is calculated using a 21% statutory federal corporate income tax rate. At or For the Three Months Ended September 30, June 30, March 31, December 31, September 30, (Dollars in thousands, except per share data) 2025 2025 2024 2024 2024 Tangible equity: Total stockholders' equity $ 1,182,776  $ 1,153,350  $ 1,137,821  $ 1,111,590  $ 1,124,972  Less: goodwill and other intangible assets 395,535  397,785  400,099  402,422  403,922  Tangible equity $ 787,241  $ 755,565  $ 737,722  $ 709,168  $ 721,050  Tangible assets: Total assets $ 9,623,944  $ 9,540,608  $ 9,246,000  $ 9,254,247  $ 9,140,471  Less: goodwill and other intangible assets 395,535  397,785  400,099  402,422  403,922  Tangible assets $ 9,228,409  $ 9,142,823  $ 8,845,901  $ 8,851,825  $ 8,736,549  Tangible book value per common share: Tangible equity $ 787,241  $ 755,565  $ 737,722  $ 709,168  $ 721,050  Common shares outstanding 35,705,369  35,673,721  35,669,100  35,563,590  35,538,607  Tangible book value per common share $ 22.05  $ 21.18  $ 20.68  $ 19.94  $ 20.29  Tangible equity to tangible assets ratio: Tangible equity $ 787,241  $ 755,565  $ 737,722  $ 709,168  $ 721,050  Tangible assets $ 9,228,409  $ 9,142,823  $ 8,845,901  $ 8,851,825  $ 8,736,549  Tangible equity to tangible assets 8.53  % 8.26  % 8.34  % 8.01  % 8.25  % Three Months Ended Nine Months Ended September 30, June 30, September 30, September 30, (Dollars in thousands) 2025 2025 2024 2025 2024 Pre-provision net revenue: Income before income taxes $ 38,002  $ 27,453  $ 40,881  $ 96,832  $ 114,609  Add: provision for credit losses 7,280  16,642  6,735  34,112  15,174  Add: net loss on investment securities 2,580  —  74  2,582  428  Add: net loss on other assets 424  267  764  1,021  1,470  Add: net loss on other transactions 54  23  28  128  92  Less: gain on OREO —  10  —  30  —  Pre-provision net revenue $ 48,340  $ 44,375  $ 48,484  $ 134,645  $ 135,121  Three Months Ended Nine Months Ended September 30, June 30, September 30, September 30, (Dollars in thousands) 2025 2025 2024 2025 2024 Annualized net income adjusted for non-core items: Net income $ 29,476  $ 21,212  $ 31,684  $ 75,024  $ 90,275  Add: net loss on investment securities 2,580  —  74  2,582  428  Less: tax effect of net loss on investment securities (a) 542  —  16  542  90  Add: net loss on asset disposals and other transactions 478  280  795  1,119  1,564  Less: tax effect of net loss on asset disposals and other transactions (a) 100  59  167  235  328  Add: acquisition-related expenses —  —  (662) —  (746) Less: tax effect of acquisition-related expenses (a) —  —  (139) —  (157) Net income adjusted for non-core items $ 31,892  $ 21,433  $ 31,847  $ 77,948  $ 91,260  Days in the period 92  91  92  273  274  Days in the year 365  365  366  365  366  Annualized net income $ 116,943  $ 85,081  $ 126,047  $ 100,307  $ 120,586  Annualized net income adjusted for non-core items $ 126,528  $ 85,968  $ 126,696  $ 104,216  $ 121,902  Return on average assets: Annualized net income $ 116,943  $ 85,081  $ 126,047  $ 100,307  $ 120,586  Total average assets $ 9,574,270  $ 9,293,287  $ 9,142,737  $ 9,355,628  $ 9,115,049  Return on average assets 1.22  % 0.92  % 1.38  % 1.07  % 1.32  % Return on average assets adjusted for non-core items: Annualized net income adjusted for non-core items $ 126,528  $ 85,968  $ 126,696  $ 104,216  $ 121,902  Total average assets $ 9,574,270  $ 9,293,287  $ 9,142,737  $ 9,355,628  $ 9,115,049  Return on average assets adjusted for non-core items 1.32  % 0.93  % 1.39  % 1.11  % 1.34  % (a) Tax effect is calculated using a 21% statutory federal corporate income tax rate. For the Three Months Ended Nine Months Ended September 30, June 30, September 30, September 30, (Dollars in thousands) 2025 2025 2024 2025 2024 Annualized net income excluding amortization of other intangible assets: Net income $ 29,476  $ 21,212  $ 31,684  $ 75,024  $ 90,275  Add: amortization of other intangible assets 2,211  2,211  2,786  6,635  8,361  Less: tax effect of amortization of other intangible assets (a) 464  464  585  1,393  1,756  Net income excluding amortization of other intangible assets $ 31,223  $ 22,959  $ 33,885  $ 80,266  $ 96,880  Days in the period 92  91  92  273  274  Days in the year 365  365  366  365  366  Annualized net income $ 116,943  $ 85,081  $ 126,047  $ 100,307  $ 120,586  Annualized net income excluding amortization of other intangible assets $ 123,874  $ 92,088  $ 134,803  $ 107,315  $ 129,409  Average tangible equity: Total average stockholders' equity $ 1,162,768  $ 1,147,253  $ 1,099,756  $ 1,144,440  $ 1,071,434  Less: average goodwill and other intangible assets 396,636  398,940  405,022  398,956  384,172  Average tangible equity $ 766,132  $ 748,313  $ 694,734  $ 745,484  $ 663,576  Return on average stockholders' equity ratio: Annualized net income $ 116,943  $ 85,081  $ 126,047  $ 100,307  $ 120,586  Average stockholders' equity $ 1,162,768  $ 1,147,253  $ 1,099,756  $ 1,144,440  $ 1,071,434  Return on average stockholders' equity 10.06  % 7.42  % 11.46  % 8.76  % 11.25  % Return on average tangible equity ratio: Annualized net income excluding amortization of other intangible assets $ 123,874  $ 92,088  $ 134,803  $ 107,315  $ 129,409  Average tangible equity $ 766,132  $ 748,313  $ 694,734  $ 745,484  $ 663,576  Return on average tangible equity 16.17  % 12.31  % 19.40  % 14.40  % 19.50  % (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 October 21, 2025 to discuss results of operations for the quarter ended September 30, 2025 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: October 27, 2025 By:/s/ KATHRYN BAILEY Kathryn Bailey Executive Vice President, Chief Financial Officer and Treasurer