Data · Sources · Reference
Utah ADU Permit Data: Sources, Counts, and the Gaps (2026)
By Utah ADU Builders Research
Last verified:
Utah ADU permit data has no single, clean statewide file. The one system that tracks accessory dwelling units (ADUs) specifically across the state is the set of moderate-income housing (MIH) reports that cities and counties file each year with the state — and those reports count ADUs so differently from one city to the next that no honest statewide total exists. We read the 2025 reports, pulled the raw numbers, and checked them against the current statutes and city records.
Most citable finding — verified July 2, 2026
In Utah’s 2025 statewide MIH reports, Alpine recorded 172 known ADUs, Bluffdale 58, and American Fork 29 — and no two of those cities counted the same way: Alpine tracks ADUs by rental licenses, American Fork by building permits, and Bluffdale by “other” (building plus administrative permits). No statewide dataset reconciles these methods, and under H.B. 436 the state paused full ADU reporting for 2026, with the next full cycle due in 2027.
Source: Utah Dept. of Workforce Services, Moderate Income Housing Program 2025 Annual Report Submissions (reporting period Aug. 1, 2024–July 31, 2025). Verified July 2, 2026.
Does Utah publish statewide ADU permit data?
Not as a single dataset. No Utah agency publishes one clean, statewide file of ADU permits. The closest ADU-specific statewide source is the annual moderate-income housing (MIH) report, in which roughly 95 cities and counties self-report ADU counts, ADU building permits, and rental licenses to the state. A separate statewide product — Utah.gov’s building-permit records — is broader than ADUs, is paid, and carries a warning that submitted records may be incomplete or delayed.
An accessory dwelling unit (ADU) is a complete, secondary home on the same lot as a single-family house: a basement or attic apartment, a garage conversion, or a standalone backyard cottage. In Utah reporting, ADUs appear under several different labels — “known ADUs,” “ADU building permits,” “business licenses to rent,” “accessory apartments” — and those labels do not mean the same thing. That mismatch is the central problem with Utah ADU data, and we return to it below.
Where does Utah ADU permit data live?
There are four official places to look, and each measures something different. The state MIH reports are the only ADU-specific statewide source; Utah.gov sells raw building-permit records; individual cities publish their own counts; and Salt Lake City publishes a dedicated annual ADU report — the deepest single-city record in the state.
| Source | Scope | ADU-specific? | Access | What it measures | Main caveat |
|---|---|---|---|---|---|
| Moderate Income Housing (MIH) reports (state) | ~95 cities & counties meeting population thresholds | Yes | Free (compiled PDFs) | Known ADUs, ADU building permits, ADU rental/business licenses, tracking method | Self-reported; tracking methods differ by city; full reporting paused for 2026 (H.B. 436) |
| "Building Permits Issued in Utah," Utah.gov | Statewide permit records submitted by cities/counties | No — all building permits | Paid | Permit number, issuing municipality, address, owner/contractor, estimated cost | Records "may be incomplete" or filed 2–4 weeks after issuance; not filtered to ADUs |
| Individual city ADU / accessory-apartment pages | Single city | Sometimes | Free | Varies — rules, application steps, occasionally counts | Not standardized; many cities post rules but no counts |
| Salt Lake City ADU Annual Report | Salt Lake City only | Yes | Free (PDF) | Applications, addresses, map, denial reasons, permit status by track | City-only; two separate approval tracks that aren't additive |
Sources: jobs.utah.gov/housing/affordable/moderate/reporting; secure.utah.gov/datarequest/buildingpermits; slc.gov/planning/adus-annual-report. Verified July 2, 2026.
The MIH program is run by the Utah Department of Workforce Services’ Housing & Community Development division; under H.B. 68 (2026) it is moving to the Governor’s Office of Economic Development, though the reporting contact remains the same. One clarification, because it trips people up: the Utah Housing Affordability Dashboard, built by the Kem C. Gardner Policy Institute with the state, does not contain ADU permit counts. It tracks affordability and deed-restricted supply — it is useful context but not an ADU data source.
What did the 2025 statewide reporting cycle show?
The 2025 MIH reports are the most recent complete statewide ADU dataset, and they show that cities count ADUs in incompatible ways. We pulled the numbers directly from the state’s compiled 2025 report for the August 1, 2024–July 31, 2025 reporting period. The sample below is limited to jurisdictions whose figures we verified line-by-line against that primary source; the full report covers roughly 95 jurisdictions.
| Jurisdiction | Total known ADUs | ADU building permits (in period) | Rental / other ADU permits (in period) | How the jurisdiction tracks ADUs |
|---|---|---|---|---|
| Alpine | 172 | 16 | 90 (business licenses to rent) | Count of business licenses/permits to rent |
| American Fork | 29 | 10 | 11 (short-term-rental licenses) | Count of building permits issued |
| Bluffdale | 58 | 5 | 8 (administrative permits) | “Other” — building + administrative land-use permits |
| Bountiful | 115 | 4 | none issued | “Other” — ADU land-use applications |
| Box Elder County | 25 | 5 | none issued | Count of conditional-use permits issued |
Source: Utah Dept. of Workforce Services, Moderate Income Housing Program 2025 Annual Report Submissions (reporting period Aug. 1, 2024–July 31, 2025). Verified July 2, 2026.
Mini-method: We read each jurisdiction’s ADU section directly in the state’s 2025 report, preserved each city’s stated tracking method, and did not add unlike metrics together. Full methodology is below.
Look down the last column. Five jurisdictions, and effectively five different counting methods — rental licenses, building permits, two flavors of “other,” and conditional-use permits. That is why the “total known ADUs” figures are not comparable: Alpine’s 172 is built from rental licenses, Bountiful’s 115 from land-use applications, Box Elder County’s 25 from conditional-use permits. A larger number does not mean more ADUs; it often just means a broader counting method or a longer history of registration.
How to pull any Utah city’s numbers. The state’s compiled reports are public. Each jurisdiction has its own section, and the ADU figures sit under a heading called “Accessory Dwelling Units.” The 2025 report and the 2024 report both open with a table of contents listing the page for every jurisdiction. Note H.B. 436: there is no full 2026 MIH reporting cycle; the next comprehensive data lands in 2027.
What Utah ADU statistics are safe to quote?
The safest Utah ADU statistics are jurisdiction-specific, dated, and labeled by metric. A figure like “Alpine reported 172 known ADUs as of its 2025 report” is defensible because it names the place, the date, and the source. A statewide total is not safe to quote, because no agency reconciles the cities’ different counting methods into one number. When in doubt, quote a single city’s figure with its metric and date attached, and link the source document.
Why aren’t Utah ADU counts comparable across cities?
Because the numbers measure different things, and cities choose different methods. A “building permit” counts construction activity in a window of time. A “known ADU” count is a running inventory that may include decades-old units. A “business license to rent” counts permission to rent, not construction. Adding these together, or comparing one city’s inventory to another’s yearly permits, produces a number that looks precise and means very little.
| Field (as it appears in state/city reports) | What it actually measures | Safe to say | Not safe to say |
|---|---|---|---|
| Total known ADUs | A running inventory of ADUs a jurisdiction is aware of, as of the report date | "As of [date], [city] recorded [N] known ADUs" | That it equals ADUs built that year, or that it’s complete |
| ADU building permits (in period) | Permits issued to construct an ADU during the reporting window | "[City] issued [N] ADU building permits between [dates]" | That every permit became a finished, occupied unit |
| Business license / permit to rent an ADU | Permission to rent; some cities don’t require one | "[City] issued [N] ADU rental licenses in [period]" | That it equals the number of ADUs, or of ADU permits |
| Conditional-use permit | An ADU approved through a public-hearing process | "[N] ADUs were approved as conditional uses" | That it’s additive with a building-permit count |
| Certificate of occupancy | Sign-off that a unit is complete and legal to occupy | "[N] units received certificates of occupancy" | That it’s an ADU-specific count (it usually isn’t) |
Compiled by Utah ADU Builders Research from the Utah MIH report fields and the Salt Lake City ADU ordinance. Verified July 2, 2026.
What does Salt Lake City’s ADU data show?
Salt Lake City keeps the deepest single-city ADU record in Utah, with one important quirk: it counts ADUs on two separate tracks that should never be added together. A 2018 ordinance requires the SLC Planning Division to publish an annual ADU report, so the city has a multi-year record no other Utah jurisdiction matches.
| Metric | Figure | Notes |
|---|---|---|
| Building-permit applications, 2018–2022 (cumulative) | 170 | Of these: 44 completed, 36 under construction, 49 in building-permit review, 41 withdrawn |
| Conditional-use ADUs approved, by year | 24 (2019), 24 (2020), 18 (2021), 20 (2022) | 86 total, 2019–2022 — a separate track from building permits |
| Average ADU size | 570 sq ft | Roughly one bedroom |
| Average ADU height | 14.5 ft | Below the city’s zoning ceiling |
Source: Salt Lake City Planning Division, 2022 ADU Annual Report (covers Jan. 1–Dec. 31, 2022). Verified July 2, 2026.
The two tracks matter: the building-permit total (170) and the conditional-use total (86) count different approval paths and can’t be summed. The city changed the rules on April 4, 2023, making ADUs a by-right use — removing the conditional-use public hearing, allowing units up to 1,000 square feet (not to exceed the main home), and waiving off-street parking near transit and bike routes. Local reporting (Building Salt Lake) found permit requests rose sharply in the months after that ordinance passed. The most current data is in the city’s annual ADU report.
What does Utah law allow — internal vs. detached ADUs?
Utah makes internal ADUs a permitted use statewide and, effective October 1, 2026, requires larger cities to allow detached ADUs on qualifying lots. The distinction is the single most important thing to get right, because state protection covers one type and not the other, and because the governing statute numbers changed in late 2025.
| ADU type | Statewide status | Governing statute (current) | Effective | What local governments may still do |
|---|---|---|---|---|
| Internal ADU (inside the primary home’s footprint) | A permitted use in areas zoned primarily for residential use, subject to statutory restrictions | §10-21-303 (municipalities); §17-80-303 (counties) | Since Oct. 1, 2021 (H.B. 82, 2021) | Restrict in up to 25% of residential area (67% for cities with a large university); require a 6,000 sq ft minimum lot; require parking; require a rental license; bar short-term rental. Construction is not subject to impact fees (§11-36a-202). |
| Detached ADU (standalone structure) | Required as a permitted use in “specified municipalities” on qualifying lots | §10-21-304 (S.B. 284, 2026) | Oct. 1, 2026 | Apply local design, parking, and setback standards; the requirement applies to lots of about 11,000 sq ft or larger that contain a single-family dwelling |
| Attached ADU (addition connected to the home) | No statewide by-right guarantee | — | — | Full local zoning discretion |
Sources: Utah Office of the Property Rights Ombudsman; Utah Legislature (le.utah.gov), incl. S.B. 284 (2026). Verified July 2, 2026. This is general information, not legal advice — confirm the current statute and your city’s ordinance before you rely on it.
Two things flow from this that most write-ups get wrong. First, the statute number: many guides still cite “Utah Code 10-9a-530” for internal ADUs. That section was renumbered to §10-21-303 effective November 6, 2025, and the old number now points to a moved provision. Second, timing on detached ADUs: S.B. 284 (sponsored by Sen. Lincoln Fillmore and Rep. Jill Koford) takes effect October 1, 2026, so as of mid-2026 it is upcoming rather than already in force everywhere. Provo has already published a parcel map showing which of its lots qualify. Until your city adopts its conforming ordinance, the local rule is what you build against.
Because the statute numbers moved, here is a crosswalk for the ADU-related citations writers most often get wrong:
| Topic | Former citation | Current citation | Note |
|---|---|---|---|
| Internal ADU — municipalities | §10-9a-530 | §10-21-303 | Renumbered Nov. 6, 2025 |
| Internal ADU — counties | §17-27a-526 | §17-80-303 | Renumbered Nov. 6, 2025 |
| Detached ADU requirement | (did not exist) | §10-21-304 | Enacted by S.B. 284; effective Oct. 1, 2026 |
| Impact-fee exemption (internal ADUs) | §11-36a-202 | §11-36a-202 | Number unchanged |
| MIH reporting — municipalities | §10-9a-408 | §10-21-201 and §10-21-202 | Renumbered Nov. 6, 2025 |
| MIH reporting — counties | §17-27a-408 | §17-80-201 and §17-80-202 | Renumbered Nov. 6, 2025 |
Source: Utah Legislature (le.utah.gov); Utah Dept. of Workforce Services. Verified July 2, 2026.
What are the detached-ADU rules by city?
Lot-size floors and other detached-ADU rules vary widely across Utah, from no minimum in Salt Lake City to 12,000 square feet in Draper. These thresholds decide whether a backyard cottage is even possible on a given lot. They are changing as cities adopt S.B. 284 ordinances, so treat this as a dated snapshot and confirm against the current municipal code.
| Jurisdiction | Min lot (detached ADU) | Max ADU size | Owner-occupancy | Short-term rental (detached) | Source |
|---|---|---|---|---|---|
| Salt Lake City | No minimum lot size | 1,000 sq ft (not to exceed primary) | Required | Prohibited | SLC Code §21A.40.200 (2023) |
| Salt Lake County (unincorporated) | 7,000 sq ft (6,000 in PC zone) | — | Owner-occupancy affidavit | — | County ordinance, June 4, 2024 |
| South Salt Lake | 6,000 sq ft | — | — | Not allowed in single-family zones | Ordinance eff. Feb. 7, 2024 |
| Millcreek | 8,000 sq ft | 1,000 sq ft | Year-round | Prohibited (detached) | Millcreek Code (eff. Nov. 15, 2021) |
| Draper | 12,000 sq ft | 50% of primary dwelling | Required | 30+ day rentals only | Draper City Planning |
| Holladay | Twice the zone’s minimum lot, or ≥ 21,780 sq ft (½ acre) | Per city chart | Owner or immediate family | — | Holladay City Code |
Sources: each jurisdiction’s municipal code / planning page. “—” indicates a value we did not confirm against the current code. Verified July 2, 2026. Confirm current thresholds with the city, as S.B. 284 ordinances are being adopted through 2026.
How we produced and verified this page
We built this page from primary sources — the state’s own reports, the enrolled statutes, and individual city records — and every Utah figure here is sourced to an official document. Where we reference news reporting, it is labeled as such and used only for context. Our process:
- We identified every official source that records Utah ADU activity and classified each as ADU-specific, general permit data, a single-city report, or a legal definition (Table 1).
- For the statewide numbers, we opened the state’s compiled 2025 Moderate Income Housing report and read the ADU section for each jurisdiction we included, using the reporting period of August 1, 2024 to July 31, 2025.
- We included a jurisdiction’s figure in Table 2 only when we could confirm it line-by-line against that primary source. Numbers we could not directly verify are not published here.
- For Salt Lake City, we read the Planning Division’s 2022 ADU Annual Report directly and preserved its two separate tracks rather than combining them.
- For the law, we relied on the current Utah Code, the Utah Office of the Property Rights Ombudsman, and the text of S.B. 284 (2026), and we noted the November 2025 statute renumbering explicitly.
Limitations — what this data does and doesn’t show
This page maps where Utah ADU data lives and reports what we verified; it does not claim a complete statewide count. The limits are part of getting it right:
- •
No statewide total. We do not publish a single “Utah ADU permit” number, because the underlying figures are not comparable and no agency reconciles them.
- •
Self-reported and uneven. MIH figures come from cities, use different tracking methods, and several jurisdictions told the state their real ADU numbers are higher than what’s registered. Read the counts as a floor.
- •
Different metrics. “Known ADUs,” “building permits,” and “rental licenses” measure different things (Table 3). Combining them would be wrong.
- •
A reporting gap ahead. Under H.B. 436, there is no full 2026 MIH reporting cycle; the next comprehensive data lands in 2027.
- •
The law is moving. S.B. 284’s detached-ADU requirement takes effect October 1, 2026, and statute numbers changed in November 2025. Confirm the current statute and your city’s ordinance.
- •
A verified sample, not the full report. Table 2 shows jurisdictions we confirmed; the state report covers roughly 95 of them, and any can be read directly using the method above.
How to cite this page
Publication: Utah ADU Builders Research
Title: Utah ADU Permit Data: Sources, Counts, and the Gaps (2026)
URL: https://utahadubuilders.com/research/utah-adu-permit-data/
Last updated:
For any city-specific number, verify the figure against the linked agency document before quoting it.
Frequently asked questions
- Does Utah publish ADU permit data?
- Not as one dataset. The state’s moderate-income housing reports collect ADU counts and ADU building permits from cities each year, and Utah.gov sells raw building-permit records, but there is no single, free, statewide ADU-only file. Full state reporting is also paused for 2026.
- How many ADUs are in Utah?
- There is no verified statewide total. City-reported figures vary widely and use different definitions — in the 2025 reports, for example, Alpine listed 172 known ADUs, Bountiful 115, and Box Elder County 25, each counting a different way. A single sum would be misleading.
- Are ADU building permits the same as rental licenses?
- No. A building permit authorizes construction; a rental (business) license authorizes renting the unit, and many Utah cities don’t require one for ADUs. They count different things and shouldn’t be added together.
- Do internal ADUs require a permit in Utah?
- Yes. Internal ADUs are a permitted use statewide, but a building permit is still required before construction, and local governments may require a registration, permit, or rental license before the unit can be rented.
- Are detached ADUs legal everywhere in Utah?
- Not yet universally. Internal ADUs have been permitted statewide since October 1, 2021. Under S.B. 284, larger “specified municipalities” must allow detached ADUs on qualifying lots (about 11,000 square feet or larger) effective October 1, 2026; until then, the local ordinance controls.
- What statute governs ADUs in Utah?
- Internal ADUs: Utah Code §10-21-303 (municipalities) and §17-80-303 (counties), renumbered from §10-9a-530 in November 2025. Detached ADUs: §10-21-304, enacted by S.B. 284 and effective October 1, 2026. ADU counts are reported to the state under §10-21-202 and §17-80-202.
- Where can I find building-permit records for a specific Utah city?
- Start with the city’s planning or building department, which often posts permit data. For a statewide view, Utah.gov offers a paid building-permit records product, though it is broader than ADUs and may lag by a few weeks.
Primary sources
- Utah Dept. of Workforce Services — Moderate Income Housing reporting — https://jobs.utah.gov/housing/affordable/moderate/reporting/
- DWS — 2025 MIH compiled report (PDF) — https://jobs.utah.gov/housing/affordable/moderate/reporting/documents/25reports.pdf
- DWS — 2024 MIH compiled report (PDF) — https://jobs.utah.gov/housing/affordable/moderate/reporting/documents/24reports.pdf
- Utah Office of the Property Rights Ombudsman — ADUs — https://commerce.utah.gov/propertyrights/find-the-law/legal-topics/adu/
- Utah Legislature — Utah Code and S.B. 284 (2026) — https://le.utah.gov
- Salt Lake City Planning Division — ADU Annual Report — https://www.slc.gov/planning/adus-annual-report/
- Salt Lake City — 2022 ADU Annual Report (PDF) — http://www.slcdocs.com/Planning/Reports/2022/ADU%202022.pdf
- Utah.gov — Building Permits Issued in Utah — https://secure.utah.gov/datarequest/buildingpermits/index.html
- Kem C. Gardner Policy Institute — Utah Housing Affordability Dashboard — https://gardner.utah.edu/affordable-housing-dashboard/
By Utah ADU Builders Research · Last verified/updated:
Utah ADU Builders maintains /research as an independent research and reference resource. This page is educational and is not legal advice; confirm current rules with your city planning department and the Utah Code.