Exhibit 99.1 Contact: Media: Lena Funston (509) 495-8090 lena.funston@avistacorp.com Investors: Stacey Wenz (509) 495-2046 stacey.wenz@avistacorp.com Avista 24/7 Media Access (509) 495-4174 Avista Corp. Reports Financial Results for the First Quarter of 2024, Confirms 2024 Earnings Guidance • First quarter consolidated earnings per diluted share of $0.91, in line with expectations • Confirms consolidated earnings guidance of $2.36 to $2.56 per diluted share | --- | --- | --- | --- | --- | |----------------- ...