Provo vs Seattle: ADU, STR & Home Business Rules Compared (2026)
Compare ADU owner-occupancy and parking rules, short-term rental permits, and home business rules between Provo, UT and Seattle, WA. Washington state law bars several local restrictions that Provo still enforces.
Side-by-Side Comparison
Provo vs Seattle
| ProvoUT | SeattleWA | |
|---|---|---|
| ADUs Allowed? | Yes — permitted use under Provo City Code Title 14 and Utah Code §10-9a-530 | Yes — required statewide under Washington HB 1337 (RCW 36.70A.681) |
| Owner Occupancy Required? | Yes — either the main dwelling unit or the ADU must be occupied by an owner occupant (Provo City Code §14.30.030(4)(a)) | No — Washington state law bars cities from requiring owner-occupancy for an ADU (RCW 36.70A.681) |
| Parking Required? | Yes — at least 4 off-street parking spaces required for a dwelling with an ADU (Provo City Code §14.30.030(5)) | No off-street parking required for an ADU (Seattle Municipal Code 23.42.022(I)) |
| STR Allowed? | No — short-term rentals are prohibited in agricultural and residential zones (Provo City Code §6.33.020(2)) | Yes — permitted in any structure established as a dwelling unit (Seattle Municipal Code 23.42.060(A)) |
| Registration Required? | No — STR use is already banned in residential zones, so no license scheme applies there | Yes — a short-term rental operator's license is required (Seattle Municipal Code 23.42.060(C)(2)) |
| Registration Type | STR business license required where STR use is otherwise allowed (Provo City Code §6.33.020) | Short-term rental operator's license (Seattle Municipal Code 23.42.060(C)(2)) |
| Home Business Allowed? | Yes — permitted with a Home Occupation Permit (Provo City Code §14.41.020) | Yes — permitted outright in all zones as an accessory use (Seattle Municipal Code 23.42.050) |
| City Permit Required? | Yes — a Home Occupation Permit must be obtained before operating (Provo City Code §14.41.020) | No — home occupations are permitted outright with no separate permit (Seattle Municipal Code 23.42.050) |
Key Differences
Provo and Seattle land on opposite sides of nearly every rule in this comparison, largely because Washington state law actively restricts what Seattle can require while Utah leaves ADU conditions to the city. Provo requires ongoing owner-occupancy of either the main house or the ADU and mandates four off-street parking spaces for any lot adding an ADU (Provo City Code §14.30.030). Seattle cannot impose either requirement — Washington's RCW 36.70A.681 (HB 1337) bars local owner-occupancy and off-street parking mandates for ADUs statewide. Short-term rentals flip the other way. Provo bans short-term rentals outright in agricultural and residential zones (Provo City Code §6.33.020(2)), while Seattle allows STR use in any dwelling unit provided the operator holds a short-term rental operator's license (Seattle Municipal Code 23.42.060). Home businesses are permitted in both cities, but Provo requires a Home Occupation Permit before starting while Seattle allows home occupations outright with no separate permit, so long as the use qualifies as accessory to the residence (Seattle Municipal Code 23.42.050).
Cost Comparison
Provo's ADU building permit fees are based on construction value and typically run $400–$2,000, plus utility connection fees; the city's consolidated fee schedule (an external document) is the authoritative source for current figures rather than a fixed total in the ordinance. Seattle's ADU building permit fees run roughly $1,500–$4,000, and Seattle School District #1 impact fees of approximately $3,700 per attached ADU and $7,400 per detached ADU may apply. Seattle has not codified a single all-in total cost estimate. Both figures are drawn from each city's fee schedule as cached at the time of research and should be confirmed with Provo Development Services and Seattle SDCI respectively before budgeting a project.
Our Verdict
For homeowners who want a rental-generating ADU with minimal restrictions, Seattle is the more permissive city: no owner-occupancy requirement, no added parking mandate, and short-term rentals are allowed with a straightforward license. Provo's rules favor owner-occupied, long-term housing over investment property — the owner-occupancy and parking requirements make an ADU harder to use purely as a rental, and the citywide STR ban in residential zones closes off that income stream entirely. If your goal is flexibility and rental income, Seattle wins; if you're building housing for family while keeping the neighborhood owner-occupied, Provo's framework matches that intent.
Explore Each City
Frequently Asked Questions
Can I rent out my ADU short-term in Provo?
No. Provo prohibits short-term rentals in agricultural and residential zones under City Code §6.33.020(2), so an ADU in a residential zone cannot be used as a short-term rental regardless of ownership.
Does Seattle require me to live in the house if I build an ADU?
No. Washington state law (RCW 36.70A.681, enacted via HB 1337) bars Seattle from requiring the property owner to occupy the ADU or any other unit on the same lot.
How many parking spaces does an ADU need in Provo vs Seattle?
Provo requires at least 4 off-street parking spaces total for a dwelling with an ADU (Provo City Code §14.30.030(5)). Seattle requires none — off-street parking cannot be required for an ADU under Seattle Municipal Code 23.42.022(I).
Do I need a permit to run a home business from my house in either city?
Provo requires a Home Occupation Permit before starting a home business (Provo City Code §14.41.020). Seattle allows home occupations outright with no separate permit, as long as the use qualifies as accessory to residential use (Seattle Municipal Code 23.42.050).
Source: PropertyZoned Editorial Research. Last verified July 3, 2026.