Washington County ADU rules by city
5 Washington County cities are covered. In 4 of them, detached backyard ADUs are generally allowed today. Each city sets its own lot size, parking and owner-occupancy rules, so check the city page before you design.
| City | County | Internal ADU | Detached ADU | Owner occupancy | S.B. 284 city | Checked |
|---|---|---|---|---|---|---|
| St. George | Washington | allowedno city lot minimum on file | allowedno city lot minimum on file | Required | Yes | ✓ 2026-09-24 |
| Washington | Washington | allowedno city lot minimum on file | allowed with conditionslot 11,000 sq ft+ | — | Yes | 2026-09-07 (not fully verified) |
| Hurricane | Washington | allowedno city lot minimum on file | allowedno city lot minimum on file | Required | Yes | ✓ 2026-09-24 |
| Ivins | Washington | allowedno city lot minimum on file | allowedno city lot minimum on file | Required | Yes | ✓ 2026-09-24 |
| Santa Clara | Washington | allowedlot 6,000 sq ft+ | allowedlot 6,000 sq ft+ | Required | Yes | ✓ 2026-09-24 |
Compare every Utah city · Check a property on the map
Unincorporated Washington County land follows county zoning, which this table does not cover. Planning information, not legal advice or a permit.