Basis of Presentation and Nature of Operations	6 Months Ended
Jun. 30, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Nature of Operations	Basis of Presentation Nature of Operations ACNB Corporation, headquartered in Gettysburg, Pennsylvania, provides banking, wealth management, mortgage and insurance services to businesses and consumers through its wholly-owned subsidiaries, ACNB Bank and ACNB Insurance Services. The Bank engages in full-service commercial and consumer banking and wealth management services, including trust and retail brokerage, through its 33 community banking offices, including 24 community banking office locations in Adams, Cumberland, Franklin, Lancaster and York Counties, Pennsylvania, and nine community banking office locations in Carroll and Frederick Counties, Maryland. There are two loan production offices located in West Lawn, Pennsylvania and in Hunt Valley, Maryland. ACNB Insurance Services is a full-service insurance agency based in Westminster, Maryland, with an additional location in Gettysburg, Pennsylvania. The agency offers a broad range of property, casualty, health, life and disability insurance to both individual and commercial clients. Recent Acquisition Effective February 1, 2025, ACNB closed the acquisition of Traditions Bancorp, Inc., holding company for Traditions Bank, York, Pennsylvania. Traditions was merged with and into a wholly-owned subsidiary of ACNB Corporation immediately followed by the merger of Traditions Bank with and into ACNB Bank. ACNB Bank is operating four of the former Traditions Bank offices as “Traditions Bank, A Division of ACNB Bank”. Basis of Financial Statements The accompanying unaudited Consolidated Financial Statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the amounts of assets and liabilities as of the date of the financial statements as well as revenues and expenses during the period. Actual results could differ from those estimates. In the opinion of management, the accompanying unaudited Consolidated Financial Statements contain all adjustments necessary for a fair presentation. All such adjustments are of a normal recurring nature. These Consolidated Financial Statements should be read in conjunction with the audited Consolidated Financial Statements and the notes included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2025. The Corporation evaluates subsequent events through the filing date of this Form 10-Q with the SEC. The results of operations for the three and six month period ended June 30, 2026, are not necessarily indicative of the results to be expected for the full year. Certain reclassifications have been made to the prior period financial statements to conform to the current period presentation. Reclassifications had no material effect on prior year net income or stockholders’ equity. Significant Accounting Policies The significant accounting policies used in preparation of the Consolidated Financial Statements are disclosed in the Corporation’s 2025 Annual Report on Form 10-K. Those significant accounting policies are unchanged at June 30, 2026. Accounting Standards Pending Adoption In November 2024, the FASB issued ASU 2024-03, “Disaggregation of Income Statement Expenses (Subtopic 220-40)”. This ASU is intended to improve the decision usefulness of expense information on public business entities’ income statements through the disaggregation of relevant expense captions in the notes to the financial statements. The amendments of ASU 2024-03 are effective for annual periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027, and early adoption is permitted. The Corporation is currently evaluating the impact of this standard, and believes that its adoption will not have a material impact on the Corporation’s Consolidated Financial Statements. In November 2025, the FASB issued ASU 2025-08, “Financial Instruments–Credit Losses (Topic 326): Purchased Loans”. The amendments in this ASU expand the population of acquired financial assets subject to the gross-up approach in Topic 326. Financial assets acquired with a “more-than-insignificant” deterioration of credit quality since its origination (PCD assets) and non-PCD assets are accounted for using the “gross up approach” to both populations. The amendments in this ASU are effective for all entities for annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual reporting periods, and early adoption is permitted. The amendments in this ASU should be applied prospectively to loans that are acquired on or after the initial application date. The Corporation is currently evaluating the impact of this standard, and believes that its adoption will not have a material impact on the Corporation’s Consolidated Financial Statements. In November 2025, the FASB issued ASU 2025-09, “Derivatives and Hedging (Topic 815): Hedge Accounting Improvements”. This ASU was issued to clarify certain aspects of the guidance on hedge accounting and to address several incremental hedge accounting issues arising from the global reference rate reform initiative. The objective of this ASU is to more closely align hedge accounting with the economics of an entity’s risk management activities. The amendments in this ASU are effective for annual reporting periods beginning after December 15, 2026, and interim periods within those annual reporting periods, and early adoption is permitted. The Corporation is currently evaluating the impact of this standard, and believes that its adoption will not have a material impact on the Corporation’s Consolidated Financial Statements. In December 2025, the FASB issued ASU 2025-11, “Interim Reporting (Topic 270): Narrow Scope Improvements”. This ASU was issued to improve the guidance in Topic 270 by improving the navigability of the required interim disclosures and clarifying when that guidance is applicable. The amendments also provide additional guidance on what disclosures should be provided in interim reporting periods. The amendments add to Topic 270 a principle that requires entities to disclose events since the end of the last annual reporting period that have a material impact on the entity. The objective of this amendment is to provide clarity on the current interim reporting requirements. The amendments in this ASU are effective for interim reporting periods within annual reporting periods beginning after December 15, 2027, and early adoption is permitted. The Corporation is currently evaluating the impact of this standard, and believes that its adoption will not have a material impact on the Corporation’s Consolidated Financial Statements.

ACNB Corporation, headquartered in Gettysburg, Pennsylvania, provides banking, wealth management, mortgage and insurance services to businesses and consumers through its wholly-owned subsidiaries, ACNB Bank and ACNB Insurance Services. The Bank engages in full-service commercial and consumer banking and wealth management services, including trust and retail brokerage, through its 33 community banking offices, including 24 community banking office locations in Adams, Cumberland, Franklin, Lancaster and York Counties, Pennsylvania, and nine community banking office locations in Carroll and Frederick Counties, Maryland. There are two loan production offices located in West Lawn, Pennsylvania and in Hunt Valley, Maryland. ACNB Insurance Services is a full-service insurance agency based in Westminster, Maryland, with an additional location in Gettysburg, Pennsylvania. The agency offers a broad range of property, casualty, health, life and disability insurance to both individual and commercial clients.

Effective February 1, 2025, ACNB closed the acquisition of Traditions Bancorp, Inc., holding company for Traditions Bank, York, Pennsylvania. Traditions was merged with and into a wholly-owned subsidiary of ACNB Corporation immediately followed by the merger of Traditions Bank with and into ACNB Bank. ACNB Bank is operating four of the former Traditions Bank offices as “Traditions Bank, A Division of ACNB Bank”.

The accompanying unaudited Consolidated Financial Statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the amounts of assets and liabilities as of the date of the financial statements as well as revenues and expenses during the period. Actual results could differ from those estimates. In the opinion of management, the accompanying unaudited Consolidated Financial Statements contain all adjustments necessary for a fair presentation. All such adjustments are of a normal recurring nature. These Consolidated Financial Statements should be read in conjunction with the audited Consolidated Financial Statements and the notes included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2025. The Corporation evaluates subsequent events through the filing date of this Form 10-Q with the SEC. The results of operations for the three and six month period ended June 30, 2026, are not necessarily indicative of the results to be expected for the full year.

In November 2024, the FASB issued ASU 2024-03, “Disaggregation of Income Statement Expenses (Subtopic 220-40)”. This ASU is intended to improve the decision usefulness of expense information on public business entities’ income statements through the disaggregation of relevant expense captions in the notes to the financial statements. The amendments of ASU 2024-03 are effective for annual periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027, and early adoption is permitted. The Corporation is currently evaluating the impact of this standard, and believes that its adoption will not have a material impact on the Corporation’s Consolidated Financial Statements.

In November 2025, the FASB issued ASU 2025-08, “Financial Instruments–Credit Losses (Topic 326): Purchased Loans”. The amendments in this ASU expand the population of acquired financial assets subject to the gross-up approach in Topic 326. Financial assets acquired with a “more-than-insignificant” deterioration of credit quality since its origination (PCD assets) and non-PCD assets are accounted for using the “gross up approach” to both populations. The amendments in this ASU are effective for all entities for annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual reporting periods, and early adoption is permitted. The amendments in this ASU should be applied prospectively to loans that are acquired on or after the initial application date. The Corporation is currently evaluating the impact of this standard, and believes that its adoption will not have a material impact on the Corporation’s Consolidated Financial Statements.

In November 2025, the FASB issued ASU 2025-09, “Derivatives and Hedging (Topic 815): Hedge Accounting Improvements”. This ASU was issued to clarify certain aspects of the guidance on hedge accounting and to address several incremental hedge accounting issues arising from the global reference rate reform initiative. The objective of this ASU is to more closely align hedge accounting with the economics of an entity’s risk management activities. The amendments in this ASU are effective for annual reporting periods beginning after December 15, 2026, and interim periods within those annual reporting periods, and early adoption is permitted. The Corporation is currently evaluating the impact of this standard, and believes that its adoption will not have a material impact on the Corporation’s Consolidated Financial Statements.