SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Mar. 31, 2026
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation Our accompanying Consolidated Financial Statements and these Notes to Consolidated Financial Statements (unaudited) include subsidiaries in which we have a controlling financial interest. We own and operate FNBPA, First National Trust Company, First National Investment Services Company, LLC, First National Insurance Agency, LLC, Bank Capital Services, LLC, F.N.B. Capital Corporation, LLC and FNB America Securities, LLC, and include results for each of these entities in the accompanying Consolidated Financial Statements. Companies in which we hold a controlling financial interest, or are a VIE in which we have the power to direct the activities of an entity that most significantly impact the entity’s economic performance and have an obligation to absorb losses or the right to receive benefits which could potentially be significant to the VIE, are consolidated. For a voting interest entity, a controlling financial interest is generally where we hold more than 50% of the outstanding voting shares. VIEs in which we do not hold the power to direct the activities of the entity that most significantly impact the entity’s economic performance and an obligation to absorb losses or the right to receive benefits which could potentially be significant to the VIE are not consolidated. Investments in companies that are not consolidated are accounted for using the equity method when we have the ability to exert significant influence. Investments in private investment partnerships that are accounted for under the equity method or the cost method are included in other assets and our proportional interest in the equity investments’ earnings are included in other non-interest income. Investment interests accounted for under the cost and equity methods are periodically evaluated for impairment. The accompanying interim unaudited Consolidated Financial Statements include all adjustments that are necessary, in the opinion of management, to fairly reflect our financial position and results of operations in accordance with GAAP. All significant intercompany balances and transactions have been eliminated. Certain prior period amounts have been reclassified to the current period presentation. Such reclassifications had no impact on our net income and shareholders' equity. Events occurring subsequent to March 31, 2026 have been evaluated for potential recognition or disclosure in the Consolidated Financial Statements through the date of the filing of the Consolidated Financial Statements with the SEC. Certain information and Note disclosures normally included in Consolidated Financial Statements prepared in accordance with GAAP have been condensed or omitted pursuant to the rules and regulations of the SEC. The interim operating results are not necessarily indicative of operating results we expect for the full year. These interim unaudited Consolidated Financial Statements should be read in conjunction with the audited Consolidated Financial Statements and Notes thereto included in our 2025 Annual Report on Form 10-K filed with the SEC on February 24, 2026. Use of Estimates Our accounting and reporting policies conform with GAAP. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the amounts reported in the Consolidated Financial Statements and accompanying Notes to Consolidated Financial Statements (unaudited). Actual results could materially differ from those estimates. Material estimates that are particularly susceptible to significant changes include the ACL, fair value of financial instruments, goodwill and other intangible assets and income taxes and deferred tax assets, which are listed in the critical accounting estimates. For a detailed description of our significant accounting policies and critical accounting estimates, see Note 1, "Summary of Significant Accounting Policies" and the "Application of Critical Accounting Policies" section in the MD&A, both in our 2025 Annual Report on Form 10-K.

FNB CORP/PA/ 10-Q