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Form 8-K

sec.gov

8-K — AVISTA CORP

Accession: 0001193125-26-329442

Filed: 2026-08-03

Period: 2026-08-01

CIK: 0000104918

SIC: 4931 (ELECTRIC & OTHER SERVICES COMBINED)

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — ava-20260801.htm (Primary)

EX-99.1 (ava-ex99_1.htm)

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8-K

8-K (Primary)

Filename: ava-20260801.htm · Sequence: 1

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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): August 01, 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. ☐

Item 8.01 Other Events.

On August 1, 2026, multiple fires started in the Spokane, Washington area, within the service territory of Avista Corporation (Avista Corp. or the Company). Dry and windy conditions have resulted in rapid spread of the fires in the Company's service territory, resulting in customer outages and evacuations. The Company's facilities were not involved in starting any of the fires in the Spokane area.

As of the evening of August 2, 2026 (and relying to some extent on reports of government agencies and external news reports), the three major fires in the Spokane area have affected over 8,000 acres and destroyed over 600 structures. At this time, none of the fires are contained. The fires have caused extensive damage to the Company's transmission and distribution facilities serving West Spokane.

Management remains focused on serving customers and supporting recovery efforts in affected communities. Further details on the fires and impacts on the Company's operations are included in the press release filed as Exhibit 99.1 to this Current Report, which is incorporated herein by reference.

Item 9.01 Financial Statements and Exhibits.

(d)

Exhibits

99.1

Press release dated August 2, 2026, which is being filed pursuant to Item 8.01.

104

Cover Page Interactive Data File (embedded within the Inline 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.

Avista Corporation

(Registrant)

Date:

August 3, 2026

By:

/s/ Gregory C. Hesler

Gregory C. Hesler

Senior Vice President, General Counsel,

Corporate Secretary and

Chief Ethics/Compliance Officer

EX-99.1

EX-99.1

Filename: ava-ex99_1.htm · Sequence: 2

EX-99.1

Exhibit 99.1

Contact:

Avista 24/7 Media Access (509) 495-4174

Wildfire damage continues to impact Avista customers

Active fires and damaged infrastructure continue to affect electric and natural gas service in parts of the Spokane area

SPOKANE, Wash., August 2, 2026 — Avista has restored service to customers affected solely by the Public Safety Power Shutoffs implemented Saturday due to extreme wildfire risk conditions across portions of Washington and Idaho. However, active wildfire conditions and significant fire-related damage continue to affect electric and natural gas service for customers in parts of the Spokane area.

In the Indian Trail area and other locations that were part of the PSPS event, customers should be aware that any remaining outages are no longer related to the Public Safety Power Shutoff. Customers who remain without power are being impacted by active wildfire conditions, damaged infrastructure, evacuation restrictions or ongoing safety concerns associated with the fires.

"We know this has been an incredibly difficult and heartbreaking weekend for many members of our community," said Heather Rosentrater, Avista president and CEO. "Many families, which include a number of Avista employees, have been forced from their homes. Neighborhoods have been impacted by these devastating fires, and thousands of customers are facing ongoing uncertainty. Our thoughts are with everyone affected. While service has been restored to customers impacted solely by the Public Safety Power Shutoff, we know that thousands of customers are still without power and for many, the hardest part may still lie ahead. As emergency responders are continuing to secure affected areas, the full extent of the damage remains unclear. Our teams are working around the clock to assess damage where we can, make repairs and restore service as quickly and safely as possible. We remain committed to supporting our customers and communities throughout the recovery process."

New development: Transmission damage may cause periodic outages

As Avista crews continue damage assessments, the company has identified significant impacts to transmission infrastructure, particularly in West Spokane. Multiple transmission lines in the area sustained damage as a result of wildfire activity. While Avista has taken steps to maintain service to as many customers as possible, customers may experience periodic power outages in the coming days as crews evaluate damage and make necessary repairs to the transmission system.

The damaged transmission system is currently operating with reduced capacity while repairs are underway. As we continue repairs, we are asking customers to voluntarily conserve energy

where practical. Small actions such as raising thermostats a few degrees, limiting the use of large appliances and turning off unnecessary lights can help reduce demand and support efforts to keep power flowing to as many customers as possible. With warmer temperatures expected in the days ahead, community-wide conservation can play an important role in supporting restoration efforts and reducing additional outages.

The situation remains dynamic and outage impacts may change as additional information becomes available. Avista will provide updates as repair plans are developed and estimated restoration timelines become clearer.

Approximately 5,300 natural gas customers remain out of service

In addition to electric system impacts, approximately 5,300 natural gas customers are currently without service due to wildfire-related damage, access restrictions and safety considerations in affected areas.

Natural gas has been shutoff in these areas, but residual gas in the lines may result in flares until the gas that remained in the pipe is consumed.

Before natural gas service can be restored, Avista crews must safely access impacted neighborhoods, complete damage assessments and ensure the integrity of the gas distribution system. In some areas, restoration activities cannot begin until fire officials determine conditions are safe and evacuation restrictions are lifted.

Restoring natural gas service is a multi-step process that requires crews to:

Inspect gas mains, services and related infrastructure for damage.

Repair or replace damaged facilities as needed.

Safely repressurize portions of the system.

Visit individual customer locations to restore service.

Relight appliances and complete required safety checks before gas service can be returned to operation.

Because each customer must be restored individually, the gas restoration process may take time, even after areas become accessible to crews. Avista has contacted peer utilities to provide support based on the extensive restoration process. Customers should not attempt to restore gas service themselves. Avista personnel will provide information and instructions directly to affected customers as restoration efforts progress.

Safety remains the top priority

Many fire-affected areas remain under evacuation orders or have limited access. As a result, Avista does not yet have a complete picture of damage to electric and natural gas infrastructure. Damage assessments will continue as emergency responders provide access to impacted neighborhoods and fire conditions allow.

Avista continues to coordinate closely with emergency management agencies, fire officials and community partners. The company appreciates the patience and cooperation of customers as crews work to assess damage and restore service where it is safe to do so.

About Avista Utilities

Avista Utilities is involved in the production, transmission and distribution of energy. We provide energy services and electricity to 429,000 customers and natural gas to 383,000 customers in a service territory that covers 34,000 square miles in eastern Washington, northern Idaho and parts of southern and eastern Oregon, with a population of 1.5 million. Avista Utilities is an operating division of Avista Corp. (NYSE: AVA). For more information, please visit www.myavista.com.

Avista Corp. and the Avista Corp. logo are trademarks of Avista Corporation.

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To unsubscribe from Avista’s news release distribution, send reply message to dalila.sheehan@avistacorp.com.

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