Rent increase rules in Washington

Washington caps annual rent increases at 9.683% for 2026 (Lesser of 10% or 7% + CPI (June 12-month CPI-U for Seattle area) (EHB 1217, 2025); manufactured/mobile-home lot rents capped at 5%). Exemptions: First 12 years after certificate of occupancy (new construction); certain owner-occupied shared dwellings and nonprofit/public housing (RCW 59.18.700 et seq.). (EHB 1217 (2025), codified in ch. 59.18 RCW (RCW 59.18.700 et seq.))

90 days' written notice for every rent increase (even cap-exempt properties), on the standardized Dept. of Commerce form; no increase during first 12 months of tenancy; income-based subsidized tenancies 30 days; Seattle requires 180 days locally. (EHB 1217 (2025), codified in ch. 59.18 RCW (RCW 59.18.700 et seq.))

No — as everywhere in the US, a fixed-term lease locks the rent unless the lease itself contains an escalation clause. Increases take effect at renewal or on periodic (month-to-month) tenancies with the notice above.

Commerce-published maximum for Jan 1-Dec 31, 2026 is 9.683%; the cap was 10% through Dec 31, 2025. Local rent caps preempted (RCW 35.21.830), but Seattle/Tacoma have stricter notice and relocation-assistance ordinances. Using the wrong notice form voids the increase; AG enforcement with penalties up to $7,500 per violation.