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ssd-202602090000920371false00009203712026-02-092026-02-09

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): February 9, 2026

Simpson Manufacturing Co., Inc. (Exact name of registrant as specified in its charter)

Delaware 1-13429 94-3196943 (State or other jurisdiction of incorporation) (Commission file number) (I.R.S. Employer Identification No.)

5956 W. Las Positas Boulevard, Pleasanton, CA 94588

(Address of principal executive offices)

(Registrant’s telephone number, including area code): (925) 560-9000

Securities registered pursuant to Section 12(b) of the Act: Title of Each ClassTrading SymbolName of Each Exchange on Which Registered Common Stock, par value $0.01 per shareSSDNew 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:

☐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-2) ☐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 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

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 2.02 Results of Operations and Financial Condition.

On February 9, 2026, Simpson Manufacturing Co., Inc. issued a press release announcing financial results for the fourth quarter and full year ended December 31, 2025, a copy of which is attached hereto as Exhibit 99.1 and is incorporated herein by this reference.

This information is furnished pursuant to Item 2.02 and shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

Item 7.01 Regulation FD Disclosures.

Representatives of Simpson Manufacturing Co., Inc. (the “Company”) intend to present the Investor Presentation furnished as Exhibit 99.2 to this Current Report on Form 8-K, to analysts and investors from time to time on or after February 9, 2026. The slide presentation will be available on the Investor Relations page of the Company’s website at ir.simpsonmfg.com.

The information furnished pursuant to this Item 7.01, including Exhibit 99.2 furnished herewith, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such a filing.

The information furnished pursuant to this Item 7.01, including Exhibit 99.2 furnished herewith, contains “forward-looking statements” within the meaning of the safe harbor provisions of the federal securities laws. It should be read in conjunction with the “Safe Harbor” statement contained in the Investor Presentation, the risk factors included in the Company’s periodic reports filed with the Securities and Exchange Commission and the other public announcements that the Company may make, by press release or otherwise, from time to time.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit No.Description

99.1Press Release dated February 9, 2026

99.2Simpson Manufacturing Co., Inc. Investor Presentation

104Cover Page Interactive Data File (embedded within the 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.

Simpson Manufacturing Co., Inc. (Registrant)

DATE:February 9, 2026By/s/ Matt Dunn Matt Dunn Chief Financial Officer

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