WA · 2026 appeal calendar

Washington Property Tax Appeal Deadlines 2026.

Washington property tax appeal deadlines and filing windows for commercial real estate. Verify with your local assessor or appeal board for the specific jurisdiction before filing.

Updated May 2026

Verify before filing. Statutory deadlines change, and many counties operate on their own schedule inside the state framework. Always confirm the current year's window with the assessor or appeal board for the specific jurisdiction before relying on a date.

2026 appeal calendar

Washington deadlines at a glance.

State-level deadlines plus major sub-jurisdictions where the schedule diverges from the state default. Where a column says "Varies," confirm the date with the local assessor.

Month Type Event Date Details
June Both
Value Notices Issued
Varies Varies locally from May-Dec
July Both
Appeal Deadline
1-Jul the later of 1) July 1 of the year of assessment 2) Within 30 days after the date an assessment or value change notice is mailed (in 31 of WA’s 39 counties) 3) Within 60 days after the date an assessment or value change notice is mailed (for the remaining 8 counties, which includes all the major metros)

RP = Real Property · BPP = Business Personal Property · Both = Applies to both

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