ESS TECH, INC

EIN 98-1550150. What DOL Form 5500 filings (EFAST2) and SEC EDGAR company filings say about this entity, with the source and date on every fact. Latest record 2026-09-03.

Employer with a benefit plan · SEC filer

ESS TECH, INC

Also filed as ACON S2 Acquisition Corp.

26440 SW PARKWAY AVE, WILSONVILLE, OR 97070

EIN

98-1550150

SEC CIK

0001819438

SEC · 2026-09-03

Industry (SIC)

Miscellaneous Electrical Machinery, Equipment & Supplies (3690)

SEC · 2026-09-03

State of incorporation

SEC · 2026-09-03

Ticker

GWH, GWHWW

SEC · 2026-09-03

Latest SEC filing

8-K 2026-09-03

SEC · 2026-09-03

Benefit plan 1, 2024 filing

ESS TECH 401(K) PLAN

DOL · 2025-10-13

Participants (start of year)

307

DOL · 2025-10-13

Plan features

code 2E2F2G2J2K2S2T3D

DOL · 2025-10-13

Plan type

Single-employer plan

DOL · 2025-10-13

Business code (NAICS)

335900

DOL · 2025-10-13

From DOL Form 5500 filings (EFAST2) · SEC EDGAR company filings. Latest record 2026-09-03.

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