Reg FD Disclosure

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): May 13, 2026     AVISTA CORPORATION (Exact name of Registrant as Specified in Its Charter)     Washington 001-03701 91-0462470 (State or Other Jurisdiction of Incorporation) (Commission File Number) (IRS Employer Identification No.)           1411 East Mission Avenue   Spokane , Washington   99202-2600 (Address of Principal Executive Offices)   (Zip Code)   Registrant’s Telephone Number, Including Area Code: 509 489-0500     (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   AVA   The 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. ☐   Section 7 – Regulation FD Item 7.01 Regulation FD Disclosure. On May 13, 2026, Avista Corporation (Avista Corp.) made available an investor presentation, which is accessible at the Company's website at https://investor.avistacorp.com. A copy of this presentation is furnished as Exhibit 99.1 to this report.     Section 9 – Financial Statements and Exhibits Item 9.01 Financial Statements and Exhibits. (d) Exhibits 99.1 May 2026 investor presentation which is being furnished pursuant to Item 7.01 104 Cover Page Interactive Data File (formatted as inline XBRL with applicable taxonomy extension information contained in Exhibits 101.)   The information contained in Item 7.01, as well as Exhibit 99.1, is “furnished” pursuant to General Instruction B2 to Form 8-K, shall not be considered “filed” for purposes of Section 18 of the Securities Exchange Act of 1934 (“Exchange Act”) and shall not be incorporated by reference into any filing under the Securities Act of 1933 (“Securities Act”) or the Exchange Act. Accordingly, such information shall not be subject to the liabilities of Section 18 of the Exchange Act or Section 11 or 12(a)(2) of the Securities Act. Neither the references to Avista Corp.’s internet website in this Current Report nor the posting of any financial presentation on such website shall, under any circumstances, be deemed to incorporate any information available on such website into this Current Report. The information available on Avista Corp.’s internet website is not part of this Current Report or any other report or other document furnished or filed by Avista Corp. with the Securities and Exchange Commission.   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 thereunto duly authorized.     AVISTA CORPORATION     (Registrant)             Date: May 13, 2026 /s/ Kevin J. Christie     Senior Vice President, Chief Financial Officer, Treasurer and Regulatory Affairs Officer