Columbia Financial, Inc.

false 0001723596 0001723596 2020-07-29 2020-07-29 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): July 1, 2026 Columbia Financial, Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-38456 22-3504946 (State or other jurisdiction (Commission (IRS Employer of incorporation) File Number) Identification Number) 19-01 Route 208 North , Fair Lawn , New Jersey 07410 (Address of principal executive offices) ( 800 ) 522-4167 (Registrant’s telephone number, including area code) 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 stock, $0.01 par value per share CLBK The Nasdaq Stock Market LLC 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 8.01 Other Events On July 1, 2026, Columbia Financial, Inc., a Delaware corporation (“ Columbia Financial ”), issued a press release announcing that at its Annual Meeting of Stockholders held on June 25, 2026, its stockholders approved the Plan of Conversion and Reorganization whereby Columbia Bank MHC, the mutual holding company of Columbia Financial and Columbia Bank (the “ MHC ”), will convert from mutual holding company form to the fully public stock holding company form (the “ Conversion ”), and approved its acquisition of Northfield Bancorp, Inc., which will occur simultaneously upon completion of the Conversion. Columbia Financial also announced that at a Special Meeting of Members of the MHC held on June 29, 2026, the depositors of Columbia Bank approved the Conversion. The press release also announced that the resolicitation of maximum purchasers in the subscription offering of Columbia Financial, Inc., a newly formed Maryland corporation and the proposed successor to Columbia Financial, concluded on June 30, 2026. A copy of the press release is filed as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference. Item 9.01 Financial Statements and Exhibits (d) Exhibits Exhibit Number Description 99.1 Press release dated July 1, 2026 104 Cover Page Interactive Data File (embedded within the Inline XBRL document) 2 SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunder duly authorized. Date: July 2, 2026 /s/Dennis E. Gibney Dennis E. Gibney 1st Senior Executive Vice President, Chief Banking Officer 3