Executive Change · Reg FD Disclosure

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): August 22, 2025   F.N.B. CORPORATION (Exact name of registrant as specified in its charter)   Pennsylvania (State or Other Jurisdiction of Incorporation) 001-31940 25-1255406 (Commission File Number) (IRS Employer Identification No.)     626 Washington Place, Pittsburgh, PA 15219 (Address of Principal Executive Offices) (Zip Code) ( 800 ) 555-5455 (Registrant's telephone number, including area code)   N/A (Former name or former address, if changed since last report) Securities registered pursuant to Section 12(b) of the Act: Title of Each Class Trading Symbol(s) Name of Exchange on which Registered Common Stock, par value $0.01 per share FNB New York Stock Exchange 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 (see General Instructions A.2. below): ☐ 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)) 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 5.02. DEPARTURE OF DIRECTORS OR CERTAIN OFFICERS; ELECTION OF DIRECTORS; APPOINTMENT OF CERTAIN OFFICERS; COMPENSATORY ARRANGEMENTS OF CERTAIN OFFICERS On August 22, 2025, Barry C. Robinson, Chief Consumer Banking Officer of F.N.B. Corporation (the “Company”), announced his intention to retire from the Company effective October 10, 2025, after 15 years of service. As part of the Company’s succession plan for executive officers, the Company announced the appointment of Alfred D. Cho as Chief Consumer Banking Officer to succeed Mr. Robinson. ITEM 7.01. REGULATION FD DISCLOSURE On August 26, 2025, the Company issued a press release announcing the upcoming retirement of Mr. Robinson and the appointment of Mr. Cho to succeed Mr. Robinson upon his retirement. A copy of the press release is attached hereto as Exhibit 99.1 and incorporated herein by reference. The information included in this Item 7.01, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended. ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS (d) Exhibits:  Exhibit Number Description 99.1 Press release dated August 26, 2025 announcing the retirement of Mr. Robinson and the appointment of Mr. Cho. 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.     F.N.B. CORPORATION   (Registrant)         By: /s/ Vincent J. Calabrese, Jr.   Name: Vincent J. Calabrese, Jr.   Title: Chief Financial Officer (Principal Financial Officer)    Dated: August 26, 2025