Boulder vs Salt Lake City: ADU, STR & Home Business Rules Compared (2026)
Compare ADU owner-occupancy and parking rules, short-term rental licensing, and home business rules between Boulder, CO and Salt Lake City, UT. Colorado's HB24-1152 ADU preemption law drives the biggest ADU differences; Salt Lake City's short-term rental rules are not independently verified in this corpus.
Side-by-Side Comparison
Boulder vs Salt Lake City
| BoulderCO | Salt Lake CityUT | |
|---|---|---|
| ADUs Allowed? | Yes — Colorado HB24-1152 requires Boulder to allow at least one ADU as an accessory use to a single-unit detached dwelling, subject to an administrative approval process (Colorado HB24-1152, CRS §29-35-403) | Yes — Salt Lake City allows and regulates ADUs to promote housing stock and choice (Salt Lake City Code §21A.40.200) |
| Owner Occupancy Required? | No ongoing requirement — Colorado HB24-1152 prohibits requiring an ADU, or any other dwelling on the same lot, to be owner-occupied on an ongoing basis, though the city may require a one-time residency demonstration at application (Colorado HB24-1152, CRS §29-35-403(2)(b)) | Yes, ongoing — the property owner must reside on the property, with limited exceptions for duplexes/multi-family/non-residential principal uses, bona fide temporary absences of 3 years or less, or medical-facility placement (Salt Lake City Code §21A.40.200(C)) |
| Parking Required? | No — Colorado HB24-1152 prohibits requiring a new off-street parking space in connection with building or converting an ADU, with limited statutory exceptions (Colorado HB24-1152, CRS §29-35-403(2)(a)) | Yes — one parking stall is required for the ADU, unless the property is in a zoning district with no minimum parking requirement, already has an extra accessible stall, or is near transit or a designated bicycle route (Salt Lake City Code §21A.40.200(G)(1)) |
| STR Allowed? | Yes — short-term rentals are prohibited unless the city manager has issued a valid short-term rental license for the property, meaning STR use is allowed under that licensing framework (Boulder Municipal Code §10-3-19) | Not independently verified — Salt Lake City's short-term rental licensing framework is referenced in the corpus but the underlying source cache is empty; see official source for Salt Lake City's current STR rules (Salt Lake City Code, STR licensing; slc.gov/planning) |
| Registration Required? | Yes — the city manager issues a rental license for short-term rental use, so registration is required to operate (Boulder Municipal Code §10-3-19) | Not independently verified — Salt Lake City's short-term rental registration requirement is not confirmed against a primary source in this corpus; see official source before assuming a registration obligation (Salt Lake City Code, STR licensing; slc.gov/planning) |
| Registration Type | Short-Term Rental License (Boulder Municipal Code §10-3-19) | Not independently verified — a 'Short-Term Rental License' label appears in Salt Lake City's cached notes but is not confirmed against a primary source; see official source for the current registration type (Salt Lake City Code, STR licensing; slc.gov/planning) |
| Home Business Allowed? | Yes — a home occupation is allowed by right if it meets the accessory-use standards (Boulder Municipal Code §9-6-3(o)) | Yes — all home occupations not specifically listed as prohibited may be permitted, subject to compliance with the code's standards (Salt Lake City Code §21A.36.030(B)) |
| City Permit Required? | No — a qualifying home occupation is allowed by right with no separate permit (Boulder Municipal Code §9-6-3(o)) | Yes — a license is required before engaging in a home occupation, obtained under Title 5, Chapter 5.02 of the city code (Salt Lake City Code §21A.36.030(E)) |
Key Differences
Boulder and Salt Lake City sit on opposite ends of Colorado's 2024 ADU preemption. Colorado HB24-1152 (Colorado House Bill 24-1152 — Accessory Dwelling Units) requires Boulder to allow at least one ADU per single-unit detached dwelling lot and prohibits the city from requiring an ADU to be owner-occupied on an ongoing basis or from requiring new off-street parking, though Boulder may ask a property owner to demonstrate residency once, at the time the application is submitted (CRS §29-35-403). Salt Lake City, operating under its own municipal code rather than a statewide ADU-preemption law, requires ongoing owner-occupancy of the property (with limited exceptions for duplexes, multi-family, temporary absences, or medical-facility placement) and one on-site parking stall unless the property qualifies for a transit, bicycle-route, or no-minimum-parking exception (Salt Lake City Code §21A.40.200). Boulder's short-term rental rules are confirmed: STR use is allowed with a city-issued license (Boulder Municipal Code §10-3-19). Salt Lake City's short-term rental posture is not independently verified in this corpus — the underlying source cache for its STR licensing framework is empty; see official source before relying on any STR detail for Salt Lake City. Home businesses are permitted in both cities, but Boulder allows a qualifying home occupation by right with no separate permit, while Salt Lake City requires a license under Title 5, Chapter 5.02 of its code before operating (Salt Lake City Code §21A.36.030(E)).
Cost Comparison
Boulder's ADU building permit fees run roughly $1,500–$5,000, plus plan-check fees of $1,000–$5,000, and Boulder Valley School District impact fees of roughly $3,000–$6,000 may apply; Colorado HB24-1152 explicitly permits municipalities to continue charging ADU impact fees (CRS §29-35-403(3)(f)). Salt Lake City's ADU permit fees typically run $1,500–$6,000, with a 4–8 week review timeline (potentially faster for internal ADUs under Utah's ministerial-approval mandate). Both figures are drawn from each city's cached fee/process notes and should be confirmed directly with Boulder Planning and Development Services or Salt Lake City Building Services before budgeting.
Our Verdict
Boulder offers substantially more legal certainty for ADU builders thanks to Colorado HB24-1152's preemption — no ongoing owner-occupancy requirement, no added parking mandate, and a state-backed right to build. Salt Lake City's tighter ADU rules (ongoing owner-occupancy, one required parking stall) suit an owner adding housing for family rather than rental income more than an investor. Short-term rental comparison isn't possible with confidence here — Boulder's STR framework is fully verified, but Salt Lake City's is not independently confirmed in this corpus, so any STR-focused buyer should check directly with Salt Lake City before assuming licensing details. On home business, Boulder's by-right approach is the lighter-touch option compared to Salt Lake City's license requirement.
Explore Each City
Frequently Asked Questions
Does Colorado's HB24-1152 mean Boulder cannot require any owner-occupancy check for an ADU?
Not quite. HB24-1152 (CRS §29-35-403(2)(b)) prohibits an ongoing owner-occupancy requirement, but it does allow Boulder to require a property owner to demonstrate residency at the time the ADU application is submitted — a one-time check, not a continuing condition.
Does Salt Lake City require ongoing owner-occupancy for an ADU?
Yes. The property owner must reside on the property, with limited exceptions for duplexes/multi-family/non-residential principal uses, bona fide temporary absences of three years or less, or medical-facility placement (Salt Lake City Code §21A.40.200(C)). Boulder, under Colorado HB24-1152, cannot impose this requirement on an ongoing basis.
Can I confirm Salt Lake City's short-term rental rules from this comparison?
Not fully — Salt Lake City's STR licensing framework is referenced in city planning materials, but the source cache backing this comparison is empty, so the details are not independently verified here; check with Salt Lake City Planning directly before relying on any STR rule. Boulder's STR framework is confirmed: a city-issued license is required (Boulder Municipal Code §10-3-19).
Which city requires more parking for an ADU, Boulder or Salt Lake City?
Salt Lake City requires one on-site parking stall unless the property qualifies for a transit, bicycle-route, or no-minimum-parking exception (Salt Lake City Code §21A.40.200(G)(1)). Boulder cannot require any new off-street parking for an ADU under Colorado HB24-1152 (CRS §29-35-403(2)(a)), with limited statutory exceptions.
Source: PropertyZoned Editorial Research. Last verified July 15, 2026.