Side by side · Utah
Compare ADU rules across Utah
Flexible on where you build? The same backyard cottage can be routine in one city and impossible in the next. This table puts 27 Utah cities side by side so you can shortlist the friendly ones before reading a single ordinance, or narrow it to just the cities you are deciding between. Every value is summarized from the city's own code; open a city's page for the full notes, citations, and fine print.
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| City | Detached ADU | Attached / internal | Max size | Owner occupancy | Extra parking | Approval |
|---|---|---|---|---|---|---|
| Alpine | Not allowed | Allowed | no explicit size cap in the ADU section | Required | 4 off-street spaces total for the lot; at least 1 designated for the ADU | In the TR-10,000, CR-20,000, CR-40,000, and CE-5 zones ADUs are a permitted use requiring an ADU permit from the Building Department (in addition to any building permits). In the CE-50 zone ADUs are listed as a conditional use requiring approval by the designated review agency. Ordinance read July 2026 |
| American Fork | Not allowed | Allowed | no explicit size cap in the ADU section | Required | 2 off-street spaces, in addition to the 2 required for the single-family home | Permitted use |
| Bluffdale | Allowed | Allowed | 50% of primary dwelling floor area | Required | 1 space (internal ADU), 2 spaces (detached ADU) | Permitted use |
| Bountiful | A detached ADU is a conditional use reviewed and approved by the Bountiful City Administrative Committee, and only in the Single-Family Residential (R), Residential Multiple (RM) Family, and Downtown (DN) Mixed Use zones. The lot must already contain a habitable single-family dwelling, must have at least 8,000 square feet of buildable land, and the property must be owner occupied; a detached ADU is unlawful on a duplex or multi-family building or property. It must sit behind the front building line and meet accessory-structure setbacks, which since Ord. 2025-13 allow either 20 feet of height with 3 foot rear and interior side setbacks (if at least 10 feet behind the front building line) or up to 25 feet with 8 foot setbacks. Utah Code 10-21-304, effective October 1, 2026, will bar the city from requiring a conditional use permit for a detached ADU in a primarily residential zone, and draft Ordinance 2026-10 would make these units staff-approved permitted uses; it had not been adopted when this entry was verified. Ordinance read August 2026 | Allowed | 1,250 sq ft, 350 sq ft minimum (detached); no explicit size cap (internal) | Required | 1 off-street space for the ADU, in addition to the principal unit's parking | Internal ADUs are a permitted use reviewed and approved by City Staff, while detached ADUs need a conditional use permit from the Bountiful City Administrative Committee; the Approval and Review Bodies table in 14-2-111 assigns detached ADU conditional use permits to the Administrative Committee as the final body and internal ADUs to Staff. It is unlawful to live in, or let anyone live in, an ADU that has not received that permit or written authorization from the Planning Department. Applications for both types, and for a short-term rental permit, are filed through the city's CityInspect portal. Under draft Ordinance 2026-10 the detached unit would move to staff review as a permitted use. Ordinance read August 2026 |
| Cedar Hills | Allowed | Allowed | no size cap in the ADU section (650 sq ft only sets the parking tier) | Required | 1 space (internal ADU); 2 spaces (detached ADU 650 sq ft or larger); 1 space (detached ADU under 650 sq ft) | Permitted use |
| Coalville | Allowed | Allowed | 1,000 sq ft or 2/3 of the primary dwelling, whichever is less (detached); no size cap stated in the IADU standards | Owner occupancy is tied to rental, not creation: renting an IADU or a DADU is not allowed unless the primary dwelling is occupied as the owner's primary residence (§03-230.C.8 and §03-230.D.9). No owner-occupancy requirement is stated for an ADU housing the owner's relatives, domestic help, or house guests. Ordinance read July 2026 | 1 on-site space in addition to the primary dwelling's parking requirement (both IADU and DADU) | Permitted use |
| Cottonwood Heights | Detached ADUs may be allowed as conditional uses in the R-1 (single-family), RR-1 (rural residential), and F-1 (foothill residential) zones; requires planning commission approval following a public hearing. Must be a permanent structure in the rear yard, set back at least 6 feet from the primary structure, and meet accessory building standards for the zone. Ordinance read July 2026 | Allowed | No explicit square-footage cap in the ADU chapter | Required | Internal ADU: 1 additional off-street space (minimum 3 total on the property); Detached ADU: 2 additional off-street spaces | Internal ADUs are permitted uses (by right, but still require an ADU application, inspection, affidavit, and annual permit renewal). Detached ADUs are conditional uses requiring planning commission approval after a public hearing, also with annual renewal. Ordinance read July 2026 |
| Draper | Allowed | Allowed | D-ADU: 50% of the single-family dwelling's total square footage (excluding garage) | Required | 1 additional off-street space | Permitted use |
| Elk Ridge | Accessory apartments may be located in a permanent accessory building associated with an owner-occupied single-family dwelling (§10-12-29(A)(2), (B)(1)); §10-12-6 permits living quarters in an accessory building only as an accessory apartment under that chapter. They are listed only as conditional uses in the residential zones (R-1-15,000, R-1-20,000, R-1-12,000, RR-1, R&L-1-20,000, HR-1, CE-2, CE-3) and are expressly not permitted in the Senior Housing Overlay Zone. §10-12-29(A)-(C); §10-12-6; §10-7A-3 and parallel zone conditional-use sectionsFull rules for Elk Ridge Ordinance read July 2026 | An accessory apartment within a single-family dwelling (a portion of the dwelling with separate cooking, sleeping and sanitary facilities per the §10-2-2 definition) may be approved subject to the §10-12-29 standards; every residential zone lists accessory apartments as a conditional use, not a permitted use (e.g. §10-7A-3), so approval is case by case. Ordinance read July 2026 | no maximum stated; 300 sq ft minimum | Required | 2 off-street spaces in addition to the primary dwelling's required spaces | Every residential zone lists accessory apartments as a conditional use (e.g. §10-7A-3), and §10-12-33 makes the CUP discretionary (approve, deny or conditionally approve against 12 factors) with mailed notice to property owners within 300 feet before the review meeting (§10-12-37). §10-12-29(B)(1) states accessory apartments may be approved by city administration upon findings of conformance, so review can be administrative rather than a planning commission hearing in most zones; in CE-3 the zone article requires Planning Commission and City Council approval (§10-9C-6-2). An accessory apartment permit plus annual renewal is also required. Ordinance read July 2026 |
| Lindon | Detached accessory apartments are allowed, but only in conjunction with an owner-occupied single-family dwelling that was not approved as part of an R2 overlay project. They are prohibited on lots of 6,000 sq ft or less and in the areas shown on the Lindon City Accessory Apartment Map, which is printed in the code and excludes single-family homes in the AFPD (Anderson Farms Planned Development), R3 and Planned Residential Development overlay zones. Detached units carry extra height, setback, size, design, and utility requirements. Separately, Utah Code 10-21-304 takes effect October 1, 2026 and will require Lindon to permit a detached accessory dwelling unit on any lot of 11,000 sq ft or larger where a single-family dwelling is a permitted use; Lindon had not amended this chapter as of its August 25, 2026 Planning Commission meeting, so ask the city how it is applying the map exclusions to detached units. Ordinance read August 2026 | Internal accessory apartments and apartments in garages or accessory buildings substantially attached to the main dwelling (by covered walkway, breezeway, or porch, within 18 feet) are allowed under the same conditions: owner-occupied single-family dwelling, lot larger than 6,000 sq ft, not in a map-prohibited area, and not part of an R2 overlay project. One accessory apartment maximum per dwelling. Ordinance read August 2026 | Detached: 1,500 sq ft or 40% of the primary dwelling, whichever is less; substantially attached (garage/accessory building): 60% of the primary dwelling footprint, max 1,200 sq ft; internal: no size restriction | Required | 1 off-street stall for an internal ADU; 2 off-street stalls for a detached or substantially attached ADU (in addition to 2 stalls for the primary dwelling) | Permitted use |
| Mapleton | An accessory apartment may be permitted in a detached building only on a lot of at least 11,000 square feet (about a quarter acre). Ordinance 2026-09, adopted June 3, 2026, cut that threshold from 21,780 square feet (half an acre) to match Utah's new detached-ADU statute. The front wall of the detached structure must sit at least 10 feet behind the front wall of the primary dwelling, and the structure must also meet the city's accessory-building standards in section 18.84.230, which cap accessory buildings at 20 percent of the rear yard, require at least 3-foot side and rear setbacks below 15 feet of height, and set maximum heights that rise with lot size. Unlike the internal-unit subsection, the detached subsection does not list eligible zones. Ordinance read August 2026 | Allowed | Detached: 1,000 to 1,400 sq ft by lot size; no maximum for internal units | Required | 1 designated off-street stall in addition to the primary dwelling's required parking | Permitted use |
| Midvale | Allowed | Allowed | Larger of 900 sq ft or 13% of lot area (EADU, cumulative with all unoccupied accessory structures) | Required | 1 space per ADU | Permitted use |
| Millcreek | Allowed | Allowed | 1,000 sq ft (detached) | Required | 1 space | Permitted use |
| Murray | Allowed | Allowed | 1,000 sq ft (detached) | Required | 1 additional space (3 total off-street) | Permitted use |
| North Salt Lake | Allowed | Allowed | 1,200 sq ft and 2 bedrooms (detached; 300 sq ft minimum); basement units may occupy the entire basement | Required | 1 additional off-street space; 1 more for ADUs with 2+ bedrooms; no tandem parking | Permitted use |
| Ogden | Allowed | Allowed | 800 sq ft (detached; 300 sq ft minimum); no explicit cap for attached or internal units | Required | No additional spaces for the ADU; the dwelling's required 2 off-street spaces must already exist | Permitted use |
| Orem | Not allowed | Accessory apartments (defined in §22-2 as a subordinate dwelling with its own eating, sleeping, and sanitation facilities within a single-family dwelling) are allowed only in owner-occupied detached single-family dwellings, and are prohibited in any R5 zone or PRD zone. Maximum one accessory apartment per dwelling (§22-6-9(I)(2)). Ordinance read July 2026 | no explicit size cap in the accessory apartment section | Required | 1 additional on-site stall (8 ft by 16 ft) for the apartment | Permitted use |
| Park City | Detached Accessory Apartments are allowed, but only on lots of 3,750 sq ft or greater: "Detached Accessory Apartments are allowed on Lots 3,750 square feet or greater." They must meet the zoning district setbacks for single-family dwellings, comply with the Area of Disturbance, Limits of Disturbance and any stricter regulation shown on the recorded plat, and "shall not exceed a maximum height of eighteen feet (18') from Existing Grade." The 15-15-1 definition also lets an Accessory Apartment be created within a detached garage. Approval is a staff-level Administrative Permit, not a hearing. Two location carve-outs matter: detached Accessory Apartments are barred inside the Holiday Ranchettes Subdivision in the Single Family (SF) district, and Accessory Apartments of any form are prohibited in HRC and HCB storefront property along Main Street and the named cross streets. The other ADU path, the Internal Accessory Dwelling Unit under 15-4-7.1, is for units inside the house only. Ordinance read August 2026 | Allowed | 1,000 sq ft and no more than 1/3 of the dwelling (Accessory Apartment); no maximum stated (Internal ADU) | It depends on which ADU type you build. For an Internal Accessory Dwelling Unit, "The Single-Family Dwelling shall be occupied by the Owner and the Internal Accessory Dwelling Unit shall not be sold separately," and the recorded deed restriction repeats that "only one (1) unit on the Property may be rented; the other must be occupied by the Owner." Section 15-4-7 states no owner-occupancy requirement for Accessory Apartments; its deed restriction instead "runs with the land and is automatically transferred to the new owner by the sale or transfer of this Property." Utah Code 10-21-303(3)(j) is what lets the city attach the owner-occupancy condition to internal units. Ordinance read August 2026 | 1 space per bedroom (Accessory Apartment); 1 space per unit (Internal ADU), both in addition to the primary dwelling | Permitted use |
| Pleasant Grove | An accessory apartment may sit in a detached accessory structure associated with a single-family dwelling, including a tiny home on a permanent site-built foundation, but only in the A-1, R-R, R-1, RM-7, DV and Grove mixed housing zones, only on an owner-occupied single-family lot, and only where the lot can supply the required off-street parking. In the R-1 zone a detached accessory structure may not exceed the height of the house or 25 feet, whichever is more restrictive, so it is held below the 35-foot main-building limit. A change is coming: Utah Code 10-21-304, enacted by S.B. 284 (2026 General Session, Chapter 166) and effective October 1, 2026, requires a specified municipality such as Pleasant Grove to permit a detached accessory dwelling unit on any lot or parcel of 11,000 square feet or larger that holds a single-family dwelling where single-family is a permitted use, and bars it from requiring a conditional use permit for one in a primarily residential zone. As of August 28, 2026 Pleasant Grove had not amended section 10-15-47 to match. §10-15-47(A), (E), (G), (S); §10-9B-9; Utah Code §10-21-304 (effective 10-1-2026)Full rules for Pleasant Grove Ordinance read August 2026 | A unit within or attached to a single-family residential building (over the garage, in the basement, or in an addition) is allowed in the A-1, R-R, R-1, RM-7, DV and Grove mixed housing zones; no accessory apartment may be in any multi-family dwelling, and the lot must satisfy the parking requirement. Utah Code 10-21-303(1)(a) independently makes an internal accessory dwelling unit a permitted use in any area zoned primarily for residential use, and Pleasant Grove's zone list already covers every primarily residential district, so the two rules line up. Watch the attached-versus-detached line: Ordinance 2026-015, adopted April 14, 2026 but not yet in the published code, replaces the section 10-6-2 definition of "Building, Attached" so that only a structure physically joined by a common wall or floor to ceiling assembly counts as attached. Under the codified definition still shown online, any two buildings six feet or less apart are deemed attached. §10-15-47(A), (E), (G); §10-6-2 as amended by Ord. 2026-015 (4-14-2026, uncodified); Utah Code §10-21-303(1)Full rules for Pleasant Grove Ordinance read August 2026 | No square-footage cap in the accessory apartment ordinance | Required | City ordinance says 6 off-street spaces (4 for the house plus 2 for the unit); state law caps what the city may require for an internal unit | Permitted use |
| Provo | A detached ADU is allowed, either as a detached accessory structure or inside one, sited in the rear and/or side yard. What limits it is the zone, not the ADU type: ADU use is a permitted use only in areas zoned primarily for residential use (RA, R1, R2, LDR, MDR, HDR, CMU, VLDR, RM, RC, any Project Redevelopment Option zone, and Specific Development Plan Overlay zones 2 through 5), and Section 14.30.020 then prohibits ADUs in all PRO zones, in R2 zones with a Performance Development Overlay (R2PD), and in areas designated RM, R16, R17, R18, R19 or R110, except where an in-code map shows an exception. West of Interstate 15, ADUs are permitted everywhere zoned primarily for residential use except SDP-5 and R2PD. Provo publishes the eligible area as an "ADU Overlay" on its Zoning Interactive Map, which is the practical way to check one address. Ordinance read August 2026 | Internal ADUs (inside the house, including a basement conversion), ADUs in an addition, and ADUs over an attached garage are all allowed, but only in conjunction with a one-family detached dwelling. They face exactly the same zone-eligibility test as detached ADUs: permitted in the zones listed in 14.30.010(3), then carved back by the 14.30.020 prohibitions covering all PRO zones, R2PD, and the mapped RM/R16 through R110 areas. An addition may not alter the one-family character of the building, and only one front entrance may be visible from the front yard. Ordinance read August 2026 | No explicit square-footage cap; a detached ADU's structure must have a smaller footprint and height than the main dwelling, and at least 200 sq ft | Required | 4 off-street spaces total for the dwelling plus ADU; two may be tandem | Permitted use |
| Salt Lake City | Allowed | Allowed | 1,000 sq ft (detached); no maximum (internal/attached) | Owner (or blood/marriage/adoption relative of a deeded owner, or family-trust trustor) must reside on the property, but owner occupancy is NOT required when the principal use is a duplex, multi-family dwelling, or non-residential use; temporary absences up to 3 years (military, job assignment, medical care) are also excepted. An owner-occupancy statement goes into a recorded restrictive covenant. Ordinance read July 2026 | 1 space, with broad waivers | Permitted use |
| Salt Lake County | Detached ADUs are a permitted use, but only on single-family home lots of 7,000 sq ft or more in areas zoned primarily for residential use (R, A, Forestry, PC zones); in the PC zone the minimum drops to 6,000 sq ft if the county has approved design standards. Not permitted in townhomes, multi-family PUDs, or other attached unit types, or on lots that cannot satisfy parking, setback, or lot coverage requirements. Ordinance read July 2026 | The code recognizes internal ADUs (IADUs) rather than attached additions: an IADU must be created within the primary dwelling and within its footprint at the time the unit is created (a garage counts if habitable and sharing a common wall). IADUs are a permitted use on single-family lots of 6,000 sq ft or more in residential zones (R, A, Forestry, PC). No category exists for an ADU added onto the house outside the existing footprint. Ordinance read July 2026 | no explicit square footage cap in the ADU chapter | Required | 1 on-site space for the ADU, in addition to the home's required parking | Permitted use |
| Sandy | Not allowed | Allowed | no explicit limit found | Required | off-street parking required | Administrative special use permit from the Community Development Department plus an accessory apartment business license (staff-level approval, not a hearing). The permit expires on sale of the property, change of the owner's residence, or business license expiration, and is not transferable. Ordinance read July 2026 |
| South Jordan | Allowed | Allowed | Guesthouse: lesser of 35% of the primary dwelling's living area or 1,500 sq ft; max 3 bedrooms | Required | 1 space | Permitted use |
| Syracuse | Detached ADUs are expressly allowed, but only in the A-1, R-1, R-2, R-3, and RPC residential zones, only on a lot with an existing (or concurrently built) single-family dwelling, and only on lots of at least 10,000 square feet; a minor conditional use permit is required. Ordinance read July 2026 | Internal (basement or attic) and attached ADUs are expressly allowed, but only in the A-1, R-1, R-2, R-3, and RPC zones on single-family lots meeting the underlying zone's minimum lot size, and a minor conditional use permit is required. Ordinance read July 2026 | 50% of principal dwelling gross sq ft (internal or attached); lesser of the main dwelling's footprint or 1,500 sq ft gross living area (detached) | Required | 1 additional off-street space (studio or one bedroom); 2 additional spaces (attached or detached with 2+ bedrooms) | A minor conditional use permit is required for every ADU. Minor conditional uses are decided administratively by the Community Development Department (no public hearing); a denial can be appealed to the Planning Commission. A building permit and a certificate of final occupancy are also required before the ADU may be occupied. Ordinance read July 2026 |
| West Bountiful | Not allowed | Allowed | No minimum or maximum size | Required | 1 additional off-street space per ADU | Permitted use |
| West Jordan | Detached ADUs (DADUs) are only permitted on platted lots of 10,000 square feet and larger in the R-1, RR, RE, PC, LSFR, and VLSFR zones; must be on a permanent foundation, footprint smaller than the primary dwelling, max height 20 feet, and design must be approved by the design review committee. Governed by this section plus Utah Code 10-21-304. Ordinance read July 2026 | Allowed | no fixed square-footage cap | Owner occupancy is not an absolute prerequisite, but it controls rental configuration: if the owner of record occupies either the primary dwelling or the ADU as a primary residence, they may rent out the other unit; if the owner occupies neither, they may rent both units together as a single unit or rent only one of the two, but may not rent both units individually at the same time (subject to Utah Code 10-21-303). Ordinance read July 2026 | 1 additional off-street space | Permitted use |
Summarized from each city's ordinance text, most recently read August 2026. Tap a value marked with an info icon to see exactly what it depends on, straight from the ordinance. Nearly every value has zone, lot-size, or process caveats beyond that; the per-city pages carry the full notes and code citations. Treat this as orientation, not a permit determination.
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Reading the table
- Detached ADU is the make-or-break column for backyard cottages: minimum lot sizes (often 8,000 to 14,500 sq ft) hide behind many of the "Allowed" values, so check your lot before celebrating.
- Attached / internal (basement apartments, additions) is legal almost everywhere and is usually the path of least resistance.
- Approval: "Permitted use" means staff-level sign-off; "Conditional use" means a public hearing, which adds time, cost, and uncertainty.
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