July 16, 2026false000211511900021151192026-06-232026-06-23

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 16, 2026

Columbia Financial, Inc.
(Exact Name of Registrant as Specified in its Charter)
Maryland333-29410342-1991301
(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 classTrading symbol(s)Name of each exchange on which registered
None

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 16, 2026, Columbia Financial, Inc., a Maryland corporation (the "Company"), issued a press release announcing the results of its firm commitment underwritten offering in connection with the second-step conversion of Columbia Financial, Inc., a Delaware corporation (the "Holding Company", along with the final subscription offering exchange ratio with respect to shares of Holding Company common stock held by the Holding Company’s minority stockholders.

The press release also announced the final merger exchange ratio in connection with the Company’s acquisition of Northfield Bancorp, Inc.

The transactions are scheduled to close on July 20, 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 NumberDescription
Press release dated July 16, 2026


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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 17, 2026/s/Dennis E. Gibney
Dennis E. Gibney
1st Senior Executive Vice President, Chief Banking Officer


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ATTACHMENTS / EXHIBITS

ATTACHMENTS / EXHIBITS

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