9Builders Original Research
How long do ADU permits actually take in San Francisco?
We analyzed every ADU permit application filed with the city since 2015 to find out. 71.2% are eventually issued, at a median of 278 days.
Get a Free QuoteWe pulled and analyzed every ADU-related building permit application filed with the City of San Francisco since 2015 — 4154 applications — to answer a question nobody publishes a real number for: how long does it actually take, and does everyone who applies eventually get a permit?
Why we are not showing you a simple year-over-year speed trend
The obvious chart to build from this data makes San Francisco look dramatically faster every year — permits filed in 2021 show a median of roughly 300 days, permits filed in 2025 show roughly 90. That chart would be misleading. A recent filing year only contains permits that have already been issued; the slow ones from that same year are still sitting in review and simply do not show up in a "days to issue" average yet. This is called right-censoring, and it makes every recent cohort look artificially fast.
So every number below is shown two ways: the speed among permits that were actually issued, and separately, what share of that year's applications have been issued at all. Read them together, not the speed number alone.
What happens to a 5-year-old application
Applications filed in 2021 or earlier have had at least five years to resolve one way or another. Here is what actually happened to all 2765 of them:
The number worth sitting with is not the 27.2% that never became a permit — it is that most of that group is not a backlog. Roughly 14.7 percentage points of it is applicants who withdrew or had the application cancelled, not applicants still waiting. Only 346 applications — 12.5% of the whole 5-year-old cohort — are genuinely still open with no outcome at all, years after filing. That is the real "stuck" number, and it is worth knowing it exists, but it is a fifth the size of the headline-looking figure.
By year filed
Full calendar years only, shown with both numbers side by side on purpose. 2026 is excluded from the table above because the year is still in progress — only 34% of that year’s 157 applications have been issued so far, which is expected for a partial year, not a slowdown.
| Year filed | Applications | Issued so far | Median days (among issued) |
|---|---|---|---|
| 2015 | 44 | 84.1% | 358 |
| 2016 | 263 | 82.1% | 537 |
| 2017 | 346 | 79.5% | 564 |
| 2018 | 434 | 73.0% | 346 |
| 2019 | 563 | 76.6% | 202 |
| 2020 | 577 | 65.9% | 430 |
| 2021 | 471 | 63.5% | 309 |
| 2022 | 428 | 65.0% | 229 |
| 2023 | 314 | 71.7% | 176 |
| 2024 | 191 | 83.2% | 35 |
| 2025 | 299 | 76.6% | 91 |
- Los Angeles — 80.9% issued, 100-day median
- San Diego — 65.8% issued, 265-day median
How we built this
Every ADU-flagged and ADU-described building permit application in DataSF's public Building Permits dataset, grouped into application families rather than individual rows. San Francisco creates a new database row for every revision and amendment filed against a permit — we confirmed this directly rather than assuming it, since treating each row as a separate application would double count and could let a same-day paperwork revision distort a duration number. For each family we take the earliest filing date and the earliest issuance date across every row in it, so a revision filed years after the original approval cannot overwrite the real issuance date with a later one.
Source: DataSF Building Permits, a public dataset published by the City and County of San Francisco. Data pulled and analyzed 2026-07-31. Methodology and the scripts that produced this analysis are described in the paragraph above; we did not alter, estimate, or exclude any application beyond the same-day filed/issued data errors disclosed in that description. This is general information, not a projection for any specific property, and 9Builders is not the City of San Francisco.