How many ADUs can I build on a Tacoma lot?
✓ Verified against code · August 19, 2026
Two, on any legally established lot regardless of size, in addition to the primary dwelling — attached, detached, or one of each.
Citation: TMC 13.06.080.A.4.a
How current is this?
Tacoma’s ADU rules run under TMC 13.06.080.A, under the Home in Tacoma Phase 2 zoning (UR-1/UR-2/UR-3) (Home in Tacoma Phase 2 (adopted Nov 19, 2024)). Home in Tacoma Phase 2, effective February 1, 2025, replaced Tacoma's single-family zoning with Urban Residential zones and folded detached ADUs into the 'Backyard Building' housing type. But Tacoma's ADU fundamentals — no parking, no owner-occupancy, DADUs citywide — date to its 2019 reform (Ord 28576), years ahead of the state mandate. Widely-read national guides still describe pre-2019 rules under fresh-looking date stamps. We verified this answer against primary sources on August 19, 2026, and every change we catch is logged in the changelog.
More Tacoma ADU questions
- Do I need off-street parking to build an ADU in Tacoma?
- Do I have to live on the property?
- How tall can a Tacoma DADU be?
- How long does a Tacoma ADU permit take?
All Tacoma ADU rules → · Compare Washington cities →
Not legal advice — lot-specific overlays can change the answer for your parcel. The citation above points at the governing code section; check it, or ask the city to confirm.