UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13A-16 OR 15D-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of February, 2026

Commission File Number: 001-37877

The Bank of N.T. Butterfield & Son Limited

(Translation of registrant’s name into English)

65 Front Street

Hamilton, HM 12

Bermuda

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F ý Form 40-F o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): o

DOCUMENTS INCLUDED AS PART OF THIS FORM 6-K

Attached hereto (i) as Exhibit 99.1 is the earnings release, (ii) as Exhibit 99.2 is the earnings call presentation, all for The Bank of N.T. Butterfield & Son Limited for the three months and year ended December 31, 2025.

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, thereunto duly authorized.


Date: February 9, 2026	THE BANK OF N.T. BUTTERFIELD & SON LIMITED


	By:	/s/ Michael Schrum
	Name:	Michael Schrum
	Title:	President and Group Chief Financial Officer


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EXHIBIT INDEX


Exhibit						Description

99.1						Earnings release - Fourth quarter and year-end 2025 results

99.2						Earnings call presentation - Fourth quarter and year-end 2025 results


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Bank of N.T. Butterfield & Son Ltd 6-K