Statistics
ADU housing supply statistics
35 of 63 figures are HyreADU calculations. What share of California’s housing accessory dwelling units actually deliver — with permitted, completed and allocated kept strictly apart.
Written by HyreADU Research Desk Primary-source research and data analysis
Audited by HyreADU Research Desk Provenance and figure-ledger audit
The short version
Accessory dwelling units are now roughly a quarter of everything California permits. They went from 9.12% of all housing units permitted and reported to HCD in 2018 to 26.52% in 2024 and 26.12% in 2025.
In 2025 the state permitted 0.89 ADU units for every single-family-detached unit, against 0.26 in 2018.
In some cities they are not a supplement to housing production but a large fraction of it. Joining HCD’s permit counts to the state’s own 6th-cycle RHNA progress file, ADUs are 52.1% of every housing unit Long Beach has permitted in its planning period, 39.1% in unincorporated Los Angeles County and 37.5% in the City of Los Angeles.
In others they are marginal: 5.5% in Fresno, 6.6% in San Francisco. The spread across these ten jurisdictions is about 9 to 1.
Measured against the allocation rather than against production, all of them are small. Long Beach’s ADU permits equal 9.7% of its total eight-year allocation, Los Angeles’s 6.3%, San Francisco’s 0.5%. Those two shares answer different questions and this page never mixes them.
Only completions are supply. Against 178,495 permit units, jurisdictions have reported 102,356 certificates of occupancy — 57.3% — and the 2018 permit cohort’s observed completion rate is 47.1% after seven years.
And no ADU on this page can be assigned to an income band. RHNA is allocated by affordability; the ADU rows in Table A2 carry no affordability field. Every share here is against a total.
Anyone telling you what share of California’s low-income obligation ADUs have met is not reading this file. 35 of 63 figures below are HyreADU calculations (35 hyreadu calculation, 25 agency published, 3 trade / survey estimate).
Three words this page keeps apart, and one it cannot use
Housing-supply arithmetic goes wrong almost entirely through vocabulary. These four constraints govern every figure below.
- Permitted is not completed
A permit is a permission. Against 178,495 ADU permit units, California jurisdictions have reported 102,356 certificates of occupancy for 2018–2025 — a cumulative 57.3%. Only the second number is housing that exists. Where this page discusses supply delivered, it uses completions; where it discusses production, it uses permits, and it says which.
- An allocation is not a target a city builds
The Regional Housing Needs Allocation assigns each jurisdiction a number of units it must plan for over an eight-year cycle.
It is a zoning and land-capacity obligation, not a construction quota, and a jurisdiction that permits less than its allocation has not necessarily failed at anything a court would recognize.
Statewide, 477,627 units of all types have been permitted against an allocation of 2,495,457 — 19.1%.
- A low ADU share is not a failing
ADUs are one housing type among several. San Francisco’s ADU share of permitted housing is low partly because San Francisco permits a great deal of multi-family housing, which is a good thing rather than a bad one. This page is not a league table and no jurisdiction on it is being graded.
- No ADU here can be assigned to an income band — and this is the important one
RHNA is allocated across four affordability categories: 642,151 very low, 384,113 low, 419,977 moderate and 1,049,216 above moderate. Table A2’s ADU rows, as this desk holds them, carry no affordability field.
So every share on this page is against a jurisdiction’s total allocation or total production, never against its very-low or low-income allocation. Saying otherwise would be the single most consequential error available on this topic, and it is one that circulates.
The statewide picture: how much of California’s housing is accessory
One table, eight years, three columns that are often conflated. Permits are permissions issued. Completions are certificates reported. The share column is the ADU fraction of every housing unit permitted in the state that year, across every unit category HCD collects.
| Year | ADU permit units | ADU completions | All housing permits reported | ADU share of permits | Class |
|---|---|---|---|---|---|
| 2018 | 12,050 | 3,186 | 131,279 | 9.12% | Agency published counts · HyreADU calculation share |
| 2019 | 12,992 | 5,957 | 124,730 | 10.31% | Agency published counts · HyreADU calculation share |
| 2020 | 13,116 | 8,065 | 115,356 | 11.22% | Agency published counts · HyreADU calculation share |
| 2021 | 21,163 | 10,147 | 137,202 | 15.19% | Agency published counts · HyreADU calculation share |
| 2022 | 26,224 | 14,043 | 139,691 | 18.49% | Agency published counts · HyreADU calculation share |
| 2023 | 29,309 | 17,676 | 137,292 | 21.05% | Agency published counts · HyreADU calculation share |
| 2024 | 31,515 | 20,652 | 116,930 | 26.52% | Agency published counts · HyreADU calculation share |
| 2025 | 32,126 | 22,630 | 120,455 | 26.12% | Agency published counts · HyreADU calculation share |
HCD APR Table A2, retrieved 2026-09-05. Permit and completion counts are agency-published; the share column is ours. Totals for the window: 178,495 permit units and 102,356 completions.
The denominator matters. This is the ADU share of all permitted housing, including multi-family.
Restricted to low-density housing the share is far higher — in 2025 California permitted 0.89 ADU units for every single-family-detached unit, against 0.26 in 2018, and both ends of that ratio moved: SFD permits fell from 45,928 to 35,424 while ADU permits rose from 11,978 to 31,460.
Permitted against completed: what has actually been delivered
The gap between the two lines is the whole reason a permit count overstates supply. It is also narrowing, which is the genuinely encouraging finding in this data: the same-year ratio rose from 26.4% in 2018 to 70.4% in 2025 as the pipeline matured and the earlier cohorts began completing.
| Measure | Figure | What it means for supply | Class |
|---|---|---|---|
| ADU permit units, 2018–2025 | 178,495 | Permissions. Not supply until built. | Agency published |
| ADU completions, 2018–2025 | 102,356 | The best available floor on delivered ADU supply in the window. | Agency published |
| Cumulative completions per permit | 57.3% | A production-accounting ratio, not a project completion rate. | HyreADU calculation |
| Same-year ratio, 2018 | 26.4% | Early cycle: permits far ahead of a young pipeline. | HyreADU calculation |
| Same-year ratio, 2025 | 70.4% | Mature cycle: completions from earlier cohorts arriving. | HyreADU calculation |
| Median permit-to-certificate lag, matched projects | 1 year | 78.9% within one year, 93.9% within two. | HyreADU calculation |
| 2018 cohort observed completion rate, 7 years on | 47.1% | A floor, not a ceiling. Unmatched is not unbuilt. | HyreADU calculation |
| 2018–2023 permit units with no matching completion | 40.9% | Still building, abandoned, unreported, or identifier changed. | HyreADU calculation |
HCD APR Table A2, retrieved 2026-09-05. Counts agency-published; ratios and cohort rates are HyreADU calculations. Method on the permits-vs-completions study.
Even 102,356 completions is a floor rather than a measurement. Reporting is incomplete in both directions, four jurisdictions never populate the completion field at all, and unpermitted ADUs — which are real housing supply — are in none of these numbers by construction. See the unpermitted-ADU page.
Ten jurisdictions, two denominators
The two share columns answer different questions and are the single easiest thing to conflate on this topic. ADU share of permitted asks: of the housing this city has actually permitted in its cycle, how much is accessory?
ADU share of allocation asks: how much of the planning obligation the state handed it do those ADUs represent? A city can be high on the first and low on the second, and most are.
| Jurisdiction | ADU permits | ADU completions | All units permitted | RHNA allocation | ADU share of permitted | ADU share of allocation | Class |
|---|---|---|---|---|---|---|---|
| Long Beach | 2,571 | 2,284 | 4,931 | 26,502 | 52.1% | 9.7% | Agency published counts · HyreADU calculation shares |
| Unincorporated Los Angeles County | 3,969 | 2,369 | 10,164 | 89,302 | 39.1% | 4.4% | Agency published counts · HyreADU calculation shares |
| Los Angeles | 28,951 | 19,514 | 77,296 | 456,643 | 37.5% | 6.3% | Agency published counts · HyreADU calculation shares |
| Unincorporated San Diego County | 1,617 | 1,302 | 6,176 | 6,700 | 26.2% | 24.1% | Agency published counts · HyreADU calculation shares |
| San Diego | 6,965 | 2,340 | 36,533 | 108,036 | 19.1% | 6.5% | Agency published counts · HyreADU calculation shares |
| Oakland | 405 | 436 | 2,535 | 26,251 | 16.0% | 1.5% | Agency published counts · HyreADU calculation shares |
| San José | 1,060 | 725 | 7,819 | 62,200 | 13.6% | 1.7% | Agency published counts · HyreADU calculation shares |
| Sacramento | 1,282 | 866 | 14,024 | 45,580 | 9.1% | 2.8% | Agency published counts · HyreADU calculation shares |
| San Francisco | 401 | 467 | 6,086 | 82,069 | 6.6% | 0.5% | Agency published counts · HyreADU calculation shares |
| Fresno | 188 | 57 | 3,415 | 36,866 | 5.5% | 0.5% | Agency published counts · HyreADU calculation shares |
HyreADU join, retrieved 2026-09-05. Cycle start dates run from April 2021 to December 2023 depending on the region, so the ADU permit window and the RHNA cycle window do not align exactly; the shares are approximations and are labeled as such throughout.
Unincorporated county rows cover unincorporated territory only and do not nest inside the city rows.
Unincorporated San Diego County is the outlier on the second column: ADU permits equal 24.1% of its allocation, against 0.5% in San Francisco. That is mostly a statement about the size of the allocations — 6,700 units against 82,069 — rather than about ADU performance. Read the denominators before reading the ranking.
The affordability question this data cannot answer
California’s 6th-cycle allocation is not one number but four. Of 2,495,457 units, 642,151 are allocated as very low income, 384,113 as low, 419,977 as moderate and 1,049,216 as above moderate. Progress against those bands is wildly uneven: 338,529 above-moderate units have been permitted against 38,748 very-low-income units.
Not one of the ADUs on this page can be placed in any of those four buckets from the data we hold. The Table A2 rows for ADUs carry no affordability field, so the arithmetic simply cannot be done. That is why every share on this page is against a total.
It matters because the most consequential policy claim in this area is precisely the one the data cannot support: that ADUs are meeting lower-income need.
There is a real argument for it — ADUs are small, they are often let below market, and Terner/CCI’s owner survey found 16 per cent of new units housing a relative at no cost — and there is a real argument against it, since an unsubsidised backyard unit in an expensive market can let at market and be counted, in RHNA terms, as above-moderate.
Both arguments are legitimate. Neither can be settled from this file, and a page that claimed to settle it would be inventing the field it needed.
What can be said honestly: ADU permits over 2022–2025 equal 4.8% of California’s entire 6th-cycle allocation, and ADU completions over 2018–2025 equal 4.1% of it. Those are shares of a total, computed across mismatched windows, and both are labeled as approximations. They are the ceiling of what this data supports.
What kind of supply is it?
Not all of it enters the rental market
Chapple, Ganetsos and Lopez, surveying California owners of ADUs permitted in 2018–19, found 51 per cent generating rental income, 16 per cent providing no-cost housing to a relative and 8 per cent used as short-term rentals. Those shares are theirs, they describe a specific cohort, and they do not sum to a hundred.
The relevance to supply accounting is direct. A unit housing an adult child rent-free is genuine housing — it removes a household from the rental market as surely as a lease does — but it is not rental supply and will never appear in a vacancy or rent statistic.
A unit let as a short-term rental is not housing supply at all in the sense a housing element means.
We use these shares to say what the production numbers cannot mean.
We do not multiply the completion count by 0.51 and present the result as "real" ADU supply: a 2021 survey of a 2018–19 cohort is not a 2026 occupancy census, and treating it as one would be exactly the kind of arithmetic this site exists not to do. See the who-lives-in-ADUs page and the rental-income study.
And a lot of it is federally invisible
The Census Building Permits Survey is the series the country uses to discuss housing production, and it cannot see an accessory dwelling unit. Four structure categories, none accessory; a conversion ADU is an alteration that records no housing units at all.
The consequence for supply accounting is not academic. In 2025, California’s own single-family-detached plus ADU permit total ran 9,145 units above the federal one-unit series for the state; in 2018 it ran 925 units below. Anyone tracking Californian housing production from the federal series alone has been missing a growing wedge of it.
And that is California, where a state series exists to reveal the gap. In the other forty-nine states the same wedge is there and there is nothing to measure it against. See the national-permit-data study.
Two different invisibilities, in opposite directions: units the federal series never counts, and units it counts without knowing what they are.
Every figure on this page, with its class
63 figures with geography, date, provenance class and source. 35 HyreADU calculations, 25 agency-published, 3 trade or survey.
| Statistic | Figure | Geography | Date | Class | Source |
|---|---|---|---|---|---|
| 6th-cycle RHNA allocation, all income bands | 2,495,457 | California, 539 jurisdictions | 6th cycle | Agency published | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 |
| Very-low-income allocation | 642,151 | California, 539 jurisdictions | 6th cycle | Agency published | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 |
| Low-income allocation | 384,113 | California, 539 jurisdictions | 6th cycle | Agency published | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 |
| Moderate-income allocation | 419,977 | California, 539 jurisdictions | 6th cycle | Agency published | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 |
| Above-moderate-income allocation | 1,049,216 | California, 539 jurisdictions | 6th cycle | Agency published | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 |
| Units of all types permitted, cycle to date | 477,627 | California, 539 jurisdictions | 6th cycle to 2025 | Agency published | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 |
| Cycle-to-date permits counted as above-moderate | 338,529 | California, 539 jurisdictions | 6th cycle to 2025 | Agency published | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 |
| Cycle-to-date permits counted as very low income | 38,748 | California, 539 jurisdictions | 6th cycle to 2025 | Agency published | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 |
| Share of the statewide allocation permitted so far | 19.1% | California, 539 jurisdictions | 6th cycle to 2025 | Agency published | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 |
| ADU building-permit units | 178,495 | California, 511 reporting jurisdictions | 2018–2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU certificates of occupancy | 102,356 | California, 511 reporting jurisdictions | 2018–2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU permit units in the 2022–2025 window | 119,174 | California, 511 reporting jurisdictions | 2022–2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| All housing permit units reported to HCD, 2025 | 120,455 | California, 511 reporting jurisdictions | 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| Single-family-detached permit units, 2025 | 35,424 | California, 511 reporting jurisdictions | 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| California 1-unit permit units, federal series, 2025 | 57,739 | California | 2025 | Agency published | U.S. Census Bureau, Building Permits Survey, annual 2025 release (14 May 2026) |
| ADU permits, cycle to date — Long Beach | 2,571 | Long Beach | 6th cycle to 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU permits, cycle to date — Unincorporated Los Angeles County | 3,969 | Unincorporated Los Angeles County | 6th cycle to 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU permits, cycle to date — Los Angeles | 28,951 | Los Angeles | 6th cycle to 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU permits, cycle to date — Unincorporated San Diego County | 1,617 | Unincorporated San Diego County | 6th cycle to 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU permits, cycle to date — San Diego | 6,965 | San Diego | 6th cycle to 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU permits, cycle to date — Oakland | 405 | Oakland | 6th cycle to 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU permits, cycle to date — San José | 1,060 | San José | 6th cycle to 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU permits, cycle to date — Sacramento | 1,282 | Sacramento | 6th cycle to 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU permits, cycle to date — San Francisco | 401 | San Francisco | 6th cycle to 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU permits, cycle to date — Fresno | 188 | Fresno | 6th cycle to 2025 | Agency published | HCD Housing Element APR, Table A2, retrieved 2026-09-05 |
| ADU share of all HCD-reported permit units, 2018 | 9.12% | California, 511 reporting jurisdictions | 2018 | HyreADU calculation | HCD Housing Element APR, Table A2, retrieved 2026-09-05 · permits-vs-completions study |
| ADU share of all HCD-reported permit units, 2024 | 26.52% | California, 511 reporting jurisdictions | 2024 | HyreADU calculation | HCD Housing Element APR, Table A2, retrieved 2026-09-05 · permits-vs-completions study |
| ADU share of all HCD-reported permit units, 2025 | 26.12% | California, 511 reporting jurisdictions | 2025 | HyreADU calculation | HCD Housing Element APR, Table A2, retrieved 2026-09-05 · permits-vs-completions study |
| Approximate ADU share of cycle-to-date permitted units | 24.9% | California, 539 jurisdictions | 2022–2025 against cycle to date | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of the statewide 6th-cycle allocation | 4.8% | California, 539 jurisdictions | 2022–2025 against 6th cycle | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| Cumulative ADU completions per permit | 57.3% | California, 511 reporting jurisdictions | 2018–2025 | HyreADU calculation | HCD Housing Element APR, Table A2, retrieved 2026-09-05 · permits-vs-completions study |
| ADU completions as a share of the statewide allocation | 4.1% | California, 539 jurisdictions | 2018–2025 against 6th cycle | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU share of cycle-to-date permitted units — Long Beach | 52.1% | Long Beach | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU share of cycle-to-date permitted units — Unincorporated Los Angeles County | 39.1% | Unincorporated Los Angeles County | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU share of cycle-to-date permitted units — Los Angeles | 37.5% | Los Angeles | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU share of cycle-to-date permitted units — Unincorporated San Diego County | 26.2% | Unincorporated San Diego County | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU share of cycle-to-date permitted units — San Diego | 19.1% | San Diego | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU share of cycle-to-date permitted units — Oakland | 16.0% | Oakland | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU share of cycle-to-date permitted units — San José | 13.6% | San José | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU share of cycle-to-date permitted units — Sacramento | 9.1% | Sacramento | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU share of cycle-to-date permitted units — San Francisco | 6.6% | San Francisco | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU share of cycle-to-date permitted units — Fresno | 5.5% | Fresno | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of allocation — Long Beach | 9.7% | Long Beach | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of allocation — Unincorporated Los Angeles County | 4.4% | Unincorporated Los Angeles County | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of allocation — Los Angeles | 6.3% | Los Angeles | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of allocation — Unincorporated San Diego County | 24.1% | Unincorporated San Diego County | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of allocation — San Diego | 6.5% | San Diego | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of allocation — Oakland | 1.5% | Oakland | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of allocation — San José | 1.7% | San José | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of allocation — Sacramento | 2.8% | Sacramento | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of allocation — San Francisco | 0.5% | San Francisco | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits as a share of allocation — Fresno | 0.5% | Fresno | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| Ratio of highest to lowest ADU production share among the ten | 9.5× | Long Beach against Fresno | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU completions in the ten jurisdictions, cycle to date | 30,360 | Ten California jurisdictions | 6th cycle to 2025 | HyreADU calculation | HCD RHNA Progress Report, 6th cycle, retrieved 2026-09-05 joined to HCD Housing Element APR, Table A2, retrieved 2026-09-05 · production-vs-need study |
| ADU permits per single-family-detached permit, 2025 | 0.89× | California, 511 reporting jurisdictions | 2025 | HyreADU calculation | HCD Housing Element APR, Table A2, retrieved 2026-09-05 · permits-vs-completions study |
| Same ratio in 2018 | 0.26× | California, 511 reporting jurisdictions | 2018 | HyreADU calculation | HCD Housing Element APR, Table A2, retrieved 2026-09-05 · permits-vs-completions study |
| ADU permits we can assign to an income band | 0 | California, 511 reporting jurisdictions | 2018–2025 | HyreADU calculation | HCD Housing Element APR, Table A2, retrieved 2026-09-05 — Table A2 ADU rows carry no affordability field |
| Matched projects completing within two years of permit | 93.9% | California, 511 reporting jurisdictions | 2018–2025 | HyreADU calculation | HCD Housing Element APR, Table A2, retrieved 2026-09-05 · permits-vs-completions study |
| 2018 permit cohort observed completion rate after seven years | 47.1% | California, 511 reporting jurisdictions | 2018 cohort | HyreADU calculation | HCD Housing Element APR, Table A2, retrieved 2026-09-05 · permits-vs-completions study |
| 2018–2023 permit units with no matching completion row | 40.9% | California, 511 reporting jurisdictions | 2018–2023 | HyreADU calculation | HCD Housing Element APR, Table A2, retrieved 2026-09-05 · permits-vs-completions study |
| New ADUs generating rental income | 51% | California, 2018–19 owner survey | Apr 2021 | Trade / survey estimate | Chapple, Ganetsos and Lopez, Center for Community Innovation, 22 April 2021 (Terner-reviewed) |
| New ADUs providing no-cost housing to a relative | 16% | California, 2018–19 owner survey | Apr 2021 | Trade / survey estimate | Chapple, Ganetsos and Lopez, Center for Community Innovation, 22 April 2021 (Terner-reviewed) |
| New ADUs used as short-term rentals | 8% | California, 2018–19 owner survey | Apr 2021 | Trade / survey estimate | Chapple, Ganetsos and Lopez, Center for Community Innovation, 22 April 2021 (Terner-reviewed) |
HyreADU calculation — computed by HyreADU, method on the production-vs-need study or the permits-vs-completions study. Agency published — printed by HCD or the Census Bureau. Trade / survey estimate — Chapple, Ganetsos and Lopez’s owner survey, cited as theirs. RHNA and APR extracts retrieved 2026-09-05.
Supply claims we will not repeat
- “ADUs have met X% of California’s affordable housing need”
This is the claim the data most clearly cannot support, and it circulates anyway. RHNA need is allocated across four income bands; the ADU rows in Table A2 carry no affordability field.
There is no arithmetic that gets from this file to an income-band share. Any figure of that shape has either substituted a total for a band or borrowed an assumption from somewhere it was not measured.
- A permit count presented as housing supply
178,495 permit units is a stock of permissions. 102,356 certificates is the floor on delivered supply, and the 2018 cohort’s observed completion rate after seven years is 47.1%. Using the permit number in a supply sentence overstates delivered housing by a factor of roughly 1.74.
- A jurisdiction ranking built on the ADU production share
5.5% in Fresno and 52.1% in Long Beach is not a difference in commitment. It reflects lot geometry, existing stock, multi-family pipeline, land values and what else the city happens to be permitting.
San Francisco’s low ADU share partly reflects the fact that it permits a great deal of apartment housing, which is what a housing element wants it to do.
- Terner’s occupancy shares applied as a haircut to production counts
The 51/16/8 split describes 2018–19 permit-cohort owners surveyed in 2021. Multiplying a 2025 completion count by 0.51 to get "real rental supply" treats a survey as a census, applies it across seven years of a changing market, and produces a number with no error bar and no owner behind it.
We cite the shares to explain what production figures cannot mean, and we do not do the multiplication.
Citing these figures
Cite the production-vs-need study rather than this digest where you can. The join method, the window mismatch between RHNA cycles and calendar years, and the affordability limitation live there in full.
For anything labeled HyreADU calculation, attribute it as "HyreADU analysis joining the California HCD Housing Element Annual Progress Report (Table A2) to the 6th-cycle RHNA Progress Report, both retrieved 5 September 2026". For anything labeled Agency published, cite HCD directly. For the occupancy shares, cite Chapple, Ganetsos and Lopez.
If you are writing about ADUs and housing need and you take one thing from this page, take the sentence about income bands. It is the difference between a defensible claim and one that will not survive the first person who opens the file.
Questions
What share of California’s new housing is ADUs?
Which California city relies on ADUs most for its housing production?
Are ADUs helping California meet its RHNA housing targets?
Do ADUs count as affordable housing under RHNA?
How many ADUs has California actually built?
Are ADUs replacing single-family homes in California’s housing mix?
Are all these ADUs adding to the rental market?
Why does the federal housing data not show this?
Does this include unpermitted ADUs?
How current is this and when does it change?
Written and audited by
HyreADU Research Desk
Primary-source research, data analysis and fact checking
We are a research desk, not a builder. We read the permit extract, the statute, the HCD return or the fee schedule ourselves, and publish each figure with its source and retrieval date.
Where a number cannot be traced to a primary source, we leave it out and say what we could not verify. Our store-based claims cover California only.
- CA
- the only state this desk will make store-based claims about
- 5
- jurisdictions with extracted ADU permit evidence
- 735
- CSLB-verified companies in the California store
- 0
- national claims from a one-state store
How this desk works
- Primary sources only. Permit counts come from the city or county that issued the permit. Production counts come from HCD’s Annual Progress Report. Rents come from HUD or the Census. We do not cite an article that cites a source; we download the source and compute the figure ourselves.
- This is a California site. The company store is 734 California firms and one New Mexico firm. Permit evidence exists for five named jurisdictions: Los Angeles, San Francisco, Sacramento, San José and unincorporated Marin. A number from that store is titled to those places, never to the United States.
- A permit is not a completion, and a license is not an ADU grade. California licenses no ADU classification. Being named on an ADU permit is evidence of engagement in that jurisdiction, not of quality, completion, or work anywhere else. Owner-builder permits are excluded from contractor counts.
- Calculation is labeled as calculation. Figures we derive are never presented as something HCD, HUD, the Census or a city published. Terner Center research is cited as Terner’s, never restated as ours.
- We do not design, permit or build ADUs, and we take no payment for placement, ranking or a favorable mention. Pages that look like rankings are not: they publish public-record counts and let the reader decide.
- Nothing here is legal, tax or financial advice. Zoning, underwriting and appraisal practice vary by jurisdiction, lender and appraiser. The useful next step on a specific lot is the planning counter and a licensed professional.
Data as of HCD RHNA Progress Report retrieved 2026-09-05 (last updated 2026-09-04T15:44:00Z); HCD APR Table A2 retrieved 2026-09-05; Census BPS annual 2025 release 14 May 2026. Authorship on this site is organizational: the analysis belongs to the desk rather than to a named individual, and we do not publish credentials we do not hold.
Our editorial policy sets out how we source, date and correct what we publish.
Sources & retrieval dates
- California HCD — RHNA Progress Report, 6th cycle , Allocations by income band and cycle-to-date permitted units for 539 jurisdictions. Statewide allocation 2,495,457 units; 477,627 permitted to date (19.1%). Last updated 2026-09-04T15:44:00Z. Retrieved 2026-09-05.
- California HCD — RHNA Progress Report CSV download , The file itself, so the join can be reproduced. Retrieved 2026-09-05.
- California HCD — Housing Element Annual Progress Report, Table A2 , 281,321 rows coded UNIT_CAT = ADU across 511 jurisdictions. The source of every ADU permit and completion count on this page. Carries no affordability field on the ADU rows. Retrieved 2026-09-05.
- California HCD — APR data dashboard , HCD’s own visualisation of the same data, useful as a cross-check. Retrieved 2026-09-05.
- U.S. Census Bureau — Building Permits Survey, annual history by state , California column, units. U.S. Census Bureau, Building Permits Survey, annual 2025 release (14 May 2026). Used only for the federal-comparison figures. Retrieved 2026-09-05.
- Chapple, Ganetsos and Lopez — Center for Community Innovation ADU owner survey (Terner-reviewed) , 51% of new ADUs generating rental income, 16% housing a relative at no cost, 8% short-term rental. A survey of 2018–19 California ADU owners, 22 April 2021. Cited as theirs and never applied as a haircut to production counts. Retrieved 2026-09-05.
Permitted, completed, allocated — three different numbers
Most bad ADU housing-supply arithmetic comes from swapping one for another. The study sets out which is which, and what none of them can tell you about affordability.
HyreADU does not design, permit or build accessory dwelling units. These statistics are informational and are not legal, planning or policy advice. Every figure describes California.
A permit is not a completed dwelling; an allocation is a planning obligation, not a construction target; and no ADU figure on this page can be assigned to an RHNA income band, because the underlying rows carry no affordability field.
Jurisdiction shares are not a ranking and a low ADU share is not a failing. Occupancy shares are attributed to the researchers who produced them and are never applied arithmetically to production counts.