WA · State directory
Washington ADU rules
Official accessory dwelling unit regulations for 17 jurisdictions in Washington, plus statewide law.
Not sure which city yet?
We have read the ordinances for 17 Washington cities and lined them up side by side: detached vs internal, size limits, owner occupancy, and approval process.
Statewide ADU law
Washington has state-level ADU legislation that applies across local jurisdictions. Local rules below may add requirements on top of state law.
Cities
Auburn4 sources · verified August 2026Bellevue5 sources · verified July 2026Bellingham6 sources · verified August 2026Everett6 sources · verified August 2026Federal Way3 sources · verified August 2026Kent4 sources · verified August 2026Kirkland4 sources · verified July 2026Olympia4 sources · verified August 2026Redmond4 sources · verified July 2026Renton5 sources · verified July 2026Seattle4 sources · verified July 2026Spokane6 sources · verified August 2026Spokane Valley4 sources · verified August 2026Tacoma6 sources · verified August 2026Vancouver5 sources · verified August 2026Yakima4 sources · verified August 2026
Counties & regions
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