Statistics

ADU approval time statistics

34 of 47 figures are HyreADU calculations. Application to permit issuance in the three California jurisdictions that publish both dates — medians and interquartile ranges, never a mean as the headline.

Updated September 2026 · Data as of LADBS pi9x-tg5x retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31); DataSF i98e-djp9 data_as_of 2026-09-04; Marin mkbn-caye rows updated 2026-09-04

Written by HyreADU Research Desk Primary-source research and data analysis

Audited by HyreADU Research Desk Provenance and figure-ledger audit

162 days Los Angeles median, application to issuance n = 27,188 issued ADU building permits, IQR 79–301 days, supplemental permits excluded. HyreADU calculation on LADBS pi9x-tg5x, retrieved 2026-09-05.

445 days San Francisco median, filed to issued n = 1,713 unique issued ADU permits, IQR 276–707 days. 62.2% of them took more than a year.

60 days statutory period — from a completed application, which no extract marks Gov. Code § 66317(a)(3). The measured medians include applicant-side delay and incomplete-submission cycles, so they are not a compliance rate against this clock.

The short version

On issued ADU building permits, the median time from application to issuance is 162 days in the City of Los Angeles (n = 27,188, interquartile range 79–301 days), 445 days in San Francisco (n = 1,713, IQR 276–707) and 175 days in unincorporated Marin (n = 472, IQR 105–308).

Those three are the only jurisdictions in this desk’s frame publishing both an application date and an issued date on ADU permits.

None of these is the statutory clock. Government Code § 66317 gives an agency 60 days to act, but that clock starts from a completed application, and no published extract marks the completeness determination.

Days spent curing an incomplete submission, paying fees or answering plan-check comments all sit inside these medians, so a median above 60 days is not evidence that a city missed the shot clock.

The spread matters more than the middle. In Los Angeles 18.9% of permits issue within 60 days and 18.8% take more than a year; in San Francisco 62.2% take more than a year.

San Francisco’s 25th percentile sits above the Los Angeles median, so three quarters of its issued ADU permits take longer than a typical Los Angeles one.

What the permit is for changes the answer more than which city it is in. Within Los Angeles, an alteration permit — usually a conversion — has a median of 102 days; a new-construction permit 218 days.

The plan-check track spans 67 days at the counter to 239 days in regular plan check.

Both large cities have got faster, and the recent-year figures are the ones to use. The Los Angeles median fell from 190 days on permits issued in 2021 to 127 days on those issued in 2025.

Grouping by year of issuance biases the most recent years fast, so read the direction rather than the size of the fall.

This is not a ranking and not a compliance rate. 34 of 47 figures below are HyreADU calculations (34 hyreadu calculation, 9 agency published, 4 trade / survey estimate).

Read this before you use any number here

Five constraints. Each one changes what the medians below are allowed to mean, and the first two are the ones that get dropped when these figures are quoted elsewhere.

Incomplete applications sit inside the clock
The statute’s 60 days start when the agency has a completed application (Gov. Code § 66317(a)(3), as amended by SB 543). None of the three extracts marks the completeness determination.
"Submitted", "filed" and "received" include every day the applicant spent curing an incomplete set, paying fees, answering plan-check comments or asking for a hold.
A median above 60 days is not by itself a finding that the city missed the shot clock, and this page never presents it as one.
These are issued permits only — the ones that never issued are invisible
Every duration here is measured on a permit that was eventually issued. Applications abandoned, withdrawn or still pending contribute nothing.
San Francisco publishes enough status detail to show the scale of that: 952 ADU-flagged records are filed and never issued, against 1,713 that carry both dates.
Selecting on the outcome makes every median on this page optimistic by an unmeasured amount.
Three jurisdictions is not California
Sacramento and San José were both opened and dropped: their published issued-permit layers carry an issued date and no application date, so no duration can be computed from them. That is the state of the data, not a judgment about those cities. The California permit-data directory lists what each Californian portal actually publishes.
The three cities do not measure the same event
Los Angeles stamps submitted_date, San Francisco filed_date, Marin received_date.
Those are three departmental practices, not one standardized milestone, and San Francisco’s ADU permits are additionally a different population — its ADU stock is overwhelmingly conversion work inside existing buildings under a local program.
Comparing the medians is legitimate; treating the difference as a pure measure of municipal speed is not.
This is not a ranking and not advice
A median is a description of permits that have already issued. It is not a prediction for your application, which depends on your parcel, your drawings, your designer and your plan checker. HyreADU does not design, permit or build accessory dwelling units.

The three jurisdictions, side by side

Medians, with the interquartile range beside each because these distributions are strongly right-skewed and a median alone hides the tail. The mean column is printed only so you can see how far the tail pulls it — it is never the headline.

The middle half of the ADU application-to-issuance distribution in each jurisdiction. LADBS pi9x-tg5x, DataSF i98e-djp9 and Marin mkbn-caye, all retrieved 2026-09-05.

Jurisdiction	Clock	Median	IQR	p10 / p90	Mean (not the headline)	n	Class
City of Los Angeles	submitted → issued	162 days	79–301 days	32 / 528	237 days	27,188	HyreADU calculation
City and County of San Francisco	filed → issued	445 days	276–707 days	168 / 1046	550 days	1,713	HyreADU calculation
Marin County (unincorporated)	received → issued	175 days	105–308 days	49 / 532	240 days	472	HyreADU calculation

HyreADU calculations on municipal open data, retrieved 2026-09-05. Los Angeles excludes supplemental permits; San Francisco is deduplicated to unique permit numbers; Marin drops trade-only rows without a building permit. Negative durations were dropped in all three and there were none.

The San Francisco median is 2.75× the Los Angeles median. Before reading that as a municipal performance gap, note that 96% of San Francisco’s ADU permits are coded "additions alterations or repairs" — conversion work in existing, often multi-family, buildings — and that San Francisco’s ADU program runs through a different local process from a Los Angeles backyard new-build.

How the distribution is shaped

The median answers "what does a typical permit do". These share columns answer the question an applicant actually has, which is "what is the chance mine takes more than a year".

Los Angeles — over a year18.8%

n = 27,188

San Francisco — over a year62.2%

n = 1,713

Unincorporated Marin — over a year17.8%

n = 472

Jurisdiction	Within 30 days	Within 60 days	Within 90 days	Within 180 days	Over a year	Class
City of Los Angeles	9.7%	18.9%	28.3%	54.8%	18.8%	HyreADU calculation
City and County of San Francisco	0.4%	0.8%	2.4%	11.5%	62.2%	HyreADU calculation
Marin County (unincorporated)	8.7%	11.7%	20.1%	51.5%	17.8%	HyreADU calculation

HyreADU calculations on the same three extracts, retrieved 2026-09-05. Shares are of issued permits, so an application that never issued is in no column.

The single most striking figure on this page is that 62.2% of San Francisco’s issued ADU permits took more than a year from filing. Excluding canceled and suspended records barely moves it: the median goes from 445 days to 443 days.

By year of issuance

Permits are grouped by the year they were issued, so a slow permit lands in the year it finished rather than the year it started. That biases recent years slightly fast — permits still in the queue are not here yet — and the bias is worst in the part year.

Median application-to-issuance days by year of issuance, three jurisdictions. LADBS pi9x-tg5x, DataSF i98e-djp9, Marin mkbn-caye, retrieved 2026-09-05.

Year issued	Los Angeles median	LA n	San Francisco median	SF n	Marin median	Marin n	Class
2020	134 days	2,551	447 days	120	154 days	32	HyreADU calculation
2021	190 days	3,641	476 days	193	154 days	50	HyreADU calculation
2022	190 days	5,092	581 days	210	187 days	56	HyreADU calculation
2023	179 days	4,220	568 days	154	213 days	69	HyreADU calculation
2024	165 days	4,196	466 days	178	158 days	57	HyreADU calculation
2025	127 days	4,569	322 days	127	235 days	98	HyreADU calculation
2026 (part year)	130 days	2,919	300 days	95	210 days	47	HyreADU calculation

HyreADU calculations, retrieved 2026-09-05. Los Angeles excludes supplementals. Marin’s annual counts are small — most years are under a hundred permits — so a single unusual project moves the median, and the year-to-year path there should be read as noisy.

Both large cities improved. Los Angeles’s 2025-issued median of 127 days is 63 days below the 2021–2022 peak of 190 days, and the share issued inside 60 days rose from 11.7% to 24.4%.

San Francisco’s fell from 581 days on 2022 issuances to 322 days on 2025 issuances.

Restricting to 2024–2026 issuances gives 143 days in Los Angeles, 392 days in San Francisco and 204 days in Marin — Marin’s recent median is higher than its long-run figure.

What is being permitted changes the clock

Within a single city, the permit type is the strongest observable predictor of approval time in this data. An alteration permit is usually a garage or interior conversion; a new-construction permit is a detached unit built from the ground up, with a foundation, a new service and a full structural review.

Bldg-Alter/Repair102 days

35.1% inside 60 days · n = 9,683

Bldg-New218 days

6.6% inside 60 days · n = 9,145

Bldg-Addition175 days

13.5% inside 60 days · n = 8,360

What the permit describes	Median	IQR	Within 60 days	n	Class
Alteration or repair (conversion)	102 days	38–203 days	35.1%	9,683	HyreADU calculation
New construction (detached ADU)	218 days	130–373 days	6.6%	9,145	HyreADU calculation
Addition (attached ADU)	175 days	94–316 days	13.5%	8,360	HyreADU calculation

HyreADU calculation on LADBS pi9x-tg5x, supplementals excluded, retrieved 2026-09-05. City of Los Angeles only.

The gap between a conversion and a new build is 116 days at the median — larger than the gap between Los Angeles and unincorporated Marin. If you want a shorter approval, the ADU type matters more than the city.

The plan-check track is the biggest single lever in the data

Los Angeles records which plan-check route a permit went through, and the spread between routes is the widest of any cut on this page: 172 days between the fastest and slowest median. The department assigns the track, largely on the complexity of the submission — it is not a service level an applicant buys.

Median application-to-issuance days by Los Angeles plan-check track. HyreADU calculation on LADBS pi9x-tg5x, retrieved 2026-09-05.

Plan-check track	Median	IQR	Within 60 days	n	Class
Expanded Counter Plan Check	128 days	63–231 days	23.7%	12,989	HyreADU calculation
Regular Plan Check	239 days	145–414 days	3.6%	10,548	HyreADU calculation
Plan Check at Counter	67 days	6–178 days	48.0%	3,442	HyreADU calculation
Appointment Plan Check	242 days	119–527 days	10.5%	209	HyreADU calculation

HyreADU calculation on LADBS pi9x-tg5x, supplementals excluded, retrieved 2026-09-05.

Read the causal direction carefully. A simple submission is routed to the counter and is quick to approve; the track is a symptom of complexity as much as a cause of speed.

What the table does establish is that the observable variation inside one department is larger than the variation between departments — which is an argument for looking at what you are submitting before looking at where.

Two things that lengthen the clock, and one that may not

Hillside, and the Coastal Zone

Los Angeles flags hillside permits, and hillside ADU permits run a median 195 days against 160 days for everything else — 35 days, on n = 1,996 hillside permits. A modest but consistent penalty for slope, grading and access review.

The Coastal Zone is a larger effect and it is measured by someone else.

Terner Center, looking at 2018–2022 planning application to building permit in three counties, found an average of 260 days inside the Coastal Zone against 147 outside in Los Angeles County, and 233 against 101 in Orange County. San Diego County showed no statistically significant difference.

Those are Terner’s figures, cited as Terner’s, and they measure a different segment from ours — the planning clock rather than the building-permit clock. They are consecutive stages of one pipeline, not competing estimates of the same thing. See the coastal-zone page.

Pre-approved plans: the claim we cannot verify

Standard-plan and pre-approved ADU programs are marketed on approval speed, and the claim is plausible: a plan the department has already reviewed should need less review. This dataset cannot confirm it.

Searching Los Angeles work descriptions for pre-approved, standard-plan, shelf-ready and prototype language finds 97 permits with a median of 114 days against the frame median of 162 days. That looks favorable and it is not evidence.

A keyword in a free-text field is not a treatment flag, the sample is a fraction of a per cent of the frame, and nothing here controls for what kind of project chooses a standard plan in the first place.

San Francisco and Marin return zero keyword matches, which tells you about their description conventions rather than about their programs. We publish the number with the caveat attached rather than suppressing it, and we do not claim a time saving. The pre-approved-plans page sets out what these programs actually promise.

A measured treatment effect would need a jurisdiction that flags standard-plan permits in its data and a comparison group matched on project type and size. We have not found one, and we will publish the moment we do.

How the Los Angeles median moves under different frames

One dataset, five defensible ways to draw the frame. The headline number is the one that excludes supplemental permits, because a supplemental electrical permit pulled the day after issuance is not an ADU approval and including it drags the median down by two months.

Frame	Median	IQR	n	Within 60 days	Class
Every ADU-flagged row, supplementals included	119 days	31–251 days	35,217	34.1%	HyreADU calculation
Supplementals excluded (headline)	162 days	79–301 days	27,188	18.9%	HyreADU calculation
Earliest non-supplemental permit per address	169 days	89–309 days	26,005	15.9%	HyreADU calculation
Issued 2024–2026 only	143 days	66–277 days	11,684	22.6%	HyreADU calculation
Pre-approved keyword match (not a treatment)	114 days	68–210 days	97	20.6%	HyreADU calculation

HyreADU calculations on LADBS pi9x-tg5x, retrieved 2026-09-05. The all-rows frame contains 3,619 permits issued the same day they were submitted — 10.3% of it — almost all of them supplemental trade permits pulled against an already-approved project. Excluding supplementals cuts that to 2.8%.

The gap between the first two rows is the whole reason this page states its frame.

A published "Los Angeles ADU permits take about four months" is defensible; so is "about five and a half months".

They are the same data with different definitions of what counts as the ADU permit, and neither is honest without the definition attached.

Every figure on this page, with its class

47 figures with geography, date, provenance class and source. 34 HyreADU calculations, 9 agency-published, 4 trade or survey.

Statistic	Figure	Geography	Date	Class	Source
Rows in the extract whose use description names an accessory dwelling	36,006	City of Los Angeles	2020–2026	Agency published	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31)
Rows carrying both a submitted and an issue date	35,224	City of Los Angeles	2020–2026	Agency published	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31)
Rows with a submitted date missing	782	City of Los Angeles	2020–2026	Agency published	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31)
Rows carrying the department’s own ADU flag	3,268	City and County of San Francisco	2015–2026	Agency published	DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04)
ADU-flagged records filed but never issued	952	City and County of San Francisco	2015–2026	Agency published	DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04)
Unique issued ADU permits with both dates	1,713	City and County of San Francisco	2015–2026	Agency published	DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04)
Description-matched ADU permits with both dates	494	Marin County (unincorporated)	2014–2026	Agency published	Marin County resource mkbn-caye, retrieved 2026-09-05 (rows updated 2026-09-04)
Trade-only rows dropped from the Marin frame	12	Marin County (unincorporated)	2014–2026	Agency published	Marin County resource mkbn-caye, retrieved 2026-09-05 (rows updated 2026-09-04)
Statutory decision period from a completed application	60 days	California	Gov. Code § 66317(a)(3)	Agency published	California Government Code § 66317, as amended by SB 543 (ADU provisions recodified out of § 65852.2)
Average days, planning application to building permit, inside the Coastal Zone	260 days	Los Angeles County	2018–2022	Trade / survey estimate	Terner Center, “ADUs in the Coastal Zone”, 2024
Average days, same measure, outside the Coastal Zone	147 days	Los Angeles County	2018–2022	Trade / survey estimate	Terner Center, “ADUs in the Coastal Zone”, 2024
Average days inside the Coastal Zone	233 days	Orange County	2018–2022	Trade / survey estimate	Terner Center, “ADUs in the Coastal Zone”, 2024
Average days outside the Coastal Zone	101 days	Orange County	2018–2022	Trade / survey estimate	Terner Center, “ADUs in the Coastal Zone”, 2024
Median days, application to permit issuance	162 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Interquartile range, application to issuance	79–301 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
10th and 90th percentile, application to issuance	32 / 528 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Mean, printed only as a contrast to the median	237 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Share issued within 60 days of application	18.9%	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Share issued within 90 days	28.3%	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Share issued within 180 days	54.8%	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Share taking more than a year	18.8%	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median including supplemental permits	119 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median on the earliest permit at each unique address	169 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median on permits issued 2024 to 2026	143 days	City of Los Angeles	2024–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median, filed to issued	445 days	City and County of San Francisco	2015–2026	HyreADU calculation	DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04) · permit-times study
Interquartile range, filed to issued	276–707 days	City and County of San Francisco	2015–2026	HyreADU calculation	DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04) · permit-times study
Share taking more than a year	62.2%	City and County of San Francisco	2015–2026	HyreADU calculation	DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04) · permit-times study
Share issued within 90 days	2.4%	City and County of San Francisco	2015–2026	HyreADU calculation	DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04) · permit-times study
Median on permits issued from 2018	469 days	City and County of San Francisco	2018–2026	HyreADU calculation	DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04) · permit-times study
Median on permits issued 2024 to 2026	392 days	City and County of San Francisco	2024–2026	HyreADU calculation	DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04) · permit-times study
Median excluding canceled and suspended permits	443 days	City and County of San Francisco	2015–2026	HyreADU calculation	DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04) · permit-times study
Median, received to issued	175 days	Marin County (unincorporated)	2018–2026	HyreADU calculation	Marin County resource mkbn-caye, retrieved 2026-09-05 (rows updated 2026-09-04) · permit-times study
Interquartile range, received to issued	105–308 days	Marin County (unincorporated)	2018–2026	HyreADU calculation	Marin County resource mkbn-caye, retrieved 2026-09-05 (rows updated 2026-09-04) · permit-times study
Share issued within 60 days	11.7%	Marin County (unincorporated)	2018–2026	HyreADU calculation	Marin County resource mkbn-caye, retrieved 2026-09-05 (rows updated 2026-09-04) · permit-times study
Median on permits issued 2024 to 2026	204 days	Marin County (unincorporated)	2024–2026	HyreADU calculation	Marin County resource mkbn-caye, retrieved 2026-09-05 (rows updated 2026-09-04) · permit-times study
San Francisco median relative to Los Angeles	2.75×	SF against LA	2015–2026 / 2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31); DataSF resource i98e-djp9, retrieved 2026-09-05 (data_as_of 2026-09-04) · permit-times study
Median, new-construction permits	218 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median, alteration or repair permits	102 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median, addition permits	175 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median, regular plan check	239 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median, expanded counter plan check	128 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median, plan check at counter	67 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median, appointment plan check	242 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median on hillside-flagged permits	195 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median on permits not hillside-flagged	160 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Difference between the fastest and slowest plan-check track	172 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · permit-times study
Median on permits whose description mentions a pre-approved or standard plan	114 days	City of Los Angeles	2020–2026	HyreADU calculation	LADBS resource pi9x-tg5x, retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31) · keyword sample of 97, not a measured treatment

HyreADU calculation — computed by HyreADU from a municipal extract, method on the permit-times study. Agency published — a frame count printed by the department, or statute. Trade / survey estimate — Terner Center’s Coastal Zone averages, cited as theirs. All municipal extracts retrieved 2026-09-05.

Approval-time claims we will not repeat

“ADUs are approved in 60 days in California”
The statute gives an agency 60 days to act on a completed application. Only 18.9% of issued Los Angeles ADU permits, 0.8% of San Francisco’s and 11.7% of unincorporated Marin’s reached issuance within 60 days of the date the department first stamped.
Those are different measurements and neither refutes the other — but quoting the statutory period as an expected wait is misleading, and quoting our medians as a compliance failure would be equally wrong.
A statewide average ADU approval time
Three jurisdictions publish the dates needed to compute one, and their medians span 175 days to 445 days. Averaging three self-selected cities into a California figure would give a number with no defensible denominator. Sacramento and San José, two of the largest ADU markets in the state, publish no application date at all.
A mean approval time
These distributions have long right tails and the mean sits far above the median in every jurisdiction — 237 days against 162 days in Los Angeles, 550 days against 445 days in San Francisco. A mean is printed here only as a contrast. Any headline "average" that is really a mean overstates the typical experience.
A time saving attributed to pre-approved plans
We can produce a number — 114 days on 97 keyword-matched permits — and we decline to present it as a finding. A free-text keyword is not a treatment flag and the sample is not a comparison group. Programs may well save time. This dataset cannot show it.

Citing these figures

Cite the permit-times study rather than this digest where you can — the frame definitions, the excluded jurisdictions and the completeness caveat live there, and a duration figure is close to meaningless without them.

For anything labeled HyreADU calculation, attribute it as "HyreADU analysis of City of Los Angeles building permits (Socrata pi9x-tg5x), retrieved 5 September 2026", substituting the relevant portal. For the Coastal Zone figures, cite Terner Center. Corrections go on the page with a dated note: hello@hyreadu.com.

And a note for anyone using this operationally: the second half of the timeline — from permit issuance to a certificate of occupancy — is a separate measurement on a separate dataset, and it is much longer than this one. See ADU construction time statistics and the construction-duration study.

Questions

How long does it take to get an ADU permit approved in California?

In the three jurisdictions that publish the dates required to answer: a median of 162 days in the City of Los Angeles (IQR 79–301, n = 27,188), 445 days in San Francisco (IQR 276–707, n = 1,713) and 175 days in unincorporated Marin (IQR 105–308, n = 472). There is no statewide figure, because most California jurisdictions do not publish an application date on issued permits.

Doesn’t state law require ADU permits to be approved in 60 days?

Government Code § 66317 requires an agency to act within 60 days, but that period runs from a completed application, and none of these datasets records when the department deemed an application complete. The measured medians therefore include time the applicant spent curing an incomplete submission, paying fees or responding to plan-check comments. 18.9% of issued Los Angeles ADU permits reached issuance inside 60 days of the submitted date. That is not a compliance rate against the statute in either direction.

Why is San Francisco so much slower than Los Angeles?

The San Francisco median (445 days) is 2.75× the Los Angeles median (162 days), and 62.2% of San Francisco’s issued ADU permits took more than a year. Some of that is process and some is population: 96% of San Francisco’s ADU permits are alterations to existing — frequently multi-family and rent-controlled — buildings, which carries tenant-protection, structural and fire review that a Los Angeles backyard new-build does not. The number is real; attributing all of it to municipal speed is not supported.

Is a garage conversion approved faster than a new detached ADU?

In Los Angeles, substantially. Alteration/repair permits — mostly conversions — run a median 102 days with 35.1% issued inside 60 days. New-construction permits run 218 days with 6.6% inside 60 days. That 116-day gap is larger than the gap between two of the three cities on this page.

Are ADU approvals getting faster?

In the two large cities, yes. The Los Angeles median on permits issued in 2025 was 127 days, against 190 days on 2021 issuances, and the share issued within 60 days rose from 11.7% to 24.4%. San Francisco fell from 581 days on 2022 issuances to 322 days on 2025 issuances — still far above Los Angeles, but moving. Unincorporated Marin runs the other way: its 2024–2026 median of 204 days is above its long-run 175 days, on annual counts small enough that the path is noisy. One caution on all three: grouping by year of issuance cannot see permits still in the queue, so the newest years are structurally flattered.

Do pre-approved or standard ADU plans speed up approval?

We cannot show that from this data, and we will not claim it. A keyword search of Los Angeles work descriptions for pre-approved and standard-plan language returns 97 permits with a median of 114 days — favorable-looking, but a free-text keyword is not a treatment flag, the sample is a fraction of a per cent of the frame, and nothing controls for what kind of project picks a standard plan. A real answer needs a jurisdiction that flags standard-plan permits in its data.

Does a hillside lot slow the permit down?

Modestly and consistently in Los Angeles: a median of 195 days on the 1,996 hillside-flagged ADU permits, against 160 days on the 25,192 that are not — a 35-day difference at the median, with a noticeably longer tail.

Why are Sacramento and San José not on this page?

Both were opened and both were dropped. Their published issued-permit layers carry an issued or status date and no application, filed or received date, so no duration can be computed from them without inventing one. That is a statement about what those portals publish, not about how those cities perform. The California permit-data directory records what each portal actually carries.

What about the time after the permit is issued?

That is the longer half. In Los Angeles the median from permit issuance to certificate of occupancy is 499 days on a censored-aware estimate — about 16.4 months — and only 35% of issued ADU permits reach a certificate within a year. Add the two medians and a Los Angeles ADU is roughly a 1.8-year undertaking from paperwork to keys. See ADU construction time statistics.

Can I use these medians to predict my own permit?

Not really, and that is not false modesty. The interquartile ranges here are wider than the medians in two of three cities, which means the middle half of applicants have wildly different experiences of the same department. Your parcel, your zone, your drawings, your designer and your plan checker will do more to determine your timeline than the city average. Use these figures to calibrate expectations and to argue with a schedule that assumes 60 days — not as a forecast.

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 LADBS pi9x-tg5x retrieved 2026-09-05 (rowsUpdatedAt 2026-08-31); DataSF i98e-djp9 data_as_of 2026-09-04; Marin mkbn-caye rows updated 2026-09-04. 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

LADBS — Building and Safety Building Permits Issued from 2020 to Present (Socrata pi9x-tg5x) , 36,006 rows whose use description names an accessory dwelling; 35,224 carry both a submitted and an issue date. Filter, exclusions and the supplemental rule are stated on the study page. Feed rowsUpdatedAt 2026-08-31. Retrieved 2026-09-05.
DataSF — Building Permits (DBI Permit Tracking System extract, i98e-djp9) , 3,268 rows carrying DBI’s own ADU flag; 1,713 unique issued permits with both a filed and an issued date; 952 filed and never issued. data_as_of 2026-09-04. Retrieved 2026-09-05.
Marin County Community Development Agency — Building Permit (mkbn-caye) , Unincorporated Marin only. 494 description-matched ADU permits with both dates, 482 kept after dropping 12 trade-only rows. Rows updated 2026-09-04. Retrieved 2026-09-05.
California Government Code § 66317 — ADU application processing , The 60-day period, running from a completed application. The ADU provisions were recodified out of § 65852.2; § 66317 is the live citation and SB 543 amended it. Retrieved 2026-09-05.
Terner Center — “ADUs in the Coastal Zone” , Average days from planning application to building permit, 2018–2022, inside against outside the Coastal Zone: Los Angeles County 260 against 147; Orange County 233 against 101; San Diego County, no statistically significant difference. Terner’s measurement of the planning clock, cited as theirs, on a different segment from ours. Retrieved 2026-09-05.
City of Sacramento open data portal , Opened and excluded: the published issued-permit layer carries a status date and a permit number, and no application or submitted date. Retrieved 2026-09-05.

A median is not your timeline

The middle half of applicants in Los Angeles wait anywhere from three to ten months. Plan against your own submission, not against a city average.

Timeline planner Read the study

HyreADU does not design, permit or build accessory dwelling units. These statistics are informational and are not legal or construction advice.

Every duration here is measured on permits that were eventually issued, so applications abandoned, withdrawn or still pending are excluded and every median is optimistic by an unmeasured amount.

None of these clocks is the statutory 60-day period, which runs from a completed application that no published extract marks; nothing here should be read as a compliance finding about any jurisdiction.

Three jurisdictions are not California, and this page is not a ranking.