Company Update

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): December 29, 2025     NATIONAL FUEL GAS COMPANY (Exact name of registrant as specified in its charter)       New Jersey   1-3880   13-1086010 (State or other jurisdiction of incorporation or organization)   (Commission File Number)   (IRS Employer Identification No.)   6363 Main Street   Williamsville , New York   14221 (Address of principal executive offices)   (Zip Code) (716) 857-7000 (Registrant’s telephone number, including area code) Not Applicable (Former name or former address, if changed since last report)     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, par value $1.00 per share   NFG   New York Stock Exchange 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 December 29, 2025, National Fuel Gas Company (the “Company”) filed a prospectus supplement (“Prospectus Supplement”) to its effective shelf registration statement on Form S-3 (Reg. No. 333-273926) filed with the Securities and Exchange Commission (the “Commission”) on August 11, 2023. The Company filed the Prospectus Supplement for the purpose of registering for resale up to 4,402,513 shares of the Company’s common stock, par value $1.00 per share (the “Common Stock”), by the selling stockholders identified in the Prospectus Supplement (the “Selling Stockholders”). The Common Stock was acquired by the Selling Stockholders in the private placement financing described in the Company’s Current Report on Form 8-K filed with the Commission on December 15, 2025. In connection with the filing of the Prospectus Supplement, the Company is filing an opinion of its counsel, Lowenstein Sandler LLP, regarding the legality of the Common Stock being registered, which opinion is attached as Exhibit 5.1 to this Current Report on Form 8-K.   Item 9.01 Financial Statements and Exhibits. (d) Exhibits.   Exhibit No.    Description 5.1    Opinion of Lowenstein Sandler LLP 23.1    Consent of Lowenstein Sandler LLP (included in Exhibit 5.1) 104    Cover Page Interactive Data File (embedded within the Inline XBRL document)     2 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. Dated: December 29, 2025   NATIONAL FUEL GAS COMPANY By:   /s/ Lee E. Hartz Name:   Lee E. Hartz Title:   General Counsel and Secretary   3