ESS Schedules Fourth Quarter and Full Year 2025 Financial Results Conference Call on Thursday, March 5, 2026 at 5:00 p.m. Eastern Time

WILSONVILLE, Ore.–(BUSINESS WIRE)–ESS Tech, Inc. (ESS) (NYSE : GWH), a leading manufacturer of iron flow long-duration energy storage (LDES) systems for commercial- and utility-scale applications, today announced that it will hold a conference call on Thursday, March 5, 2026 at 5:00 p.m. EST to discuss financial results for its fourth quarter and full year 2025 ended December 31, 2025, and will be providing updates on recent organizational changes, commercial progress and customer deployments, and strategic priorities going forward. A press release detailing these results will be issued prior to the call.

ESS Tech CEO Drew Buckley and CFO Kate Suhadolnik will host the conference call, followed by a question-and-answer period. The conference call will be accompanied by a presentation, which can be viewed or access following the call via the investor relations section of the Company’s website here.

To access the call, please use the following information:

Date:		Thursday, March 5, 2026
Time:		5:00 p.m. Eastern Time (2:00 p.m. Pacific Time)
Dial-in:		1-833-470-1428
International Dial-in:		1-646-844-6383
Conference Code:		547200
Webcast:		https://events.q4inc.com/attendee/987783929

A telephone replay will be available through March 12, 2026, by dialing 1-866-813-9403 from the U.S., or 1-929-458-6194 from international locations, and entering replay pin number: 217487. The replay can also be viewed through the webcast link above and the presentation utilized during the call will be available via the investor relations section of the Company’s website here.

About ESS Tech, Inc.

ESS (NYSE: GWH) is the leading manufacturer of long-duration iron flow energy storage solutions. ESS was established in 2011 with a mission to accelerate decarbonization safely and sustainably through longer lasting energy storage. Using easy-to-source iron, salt, and water, ESS iron flow technology enables energy security, reliability and resilience. We build flexible storage solutions that allow our customers to meet increasing energy demand without power disruptions and maximize the value potential of excess energy. For more information visit www.essinc.com.

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