Key findings
- Ventura County's cities and unincorporated areas reported 923 ADU building permits in 2025, up from 275 in 2020.
- Oxnard reported the most: 888 of 3,705 permits from 2018 to 2025 (24%).
- Countywide, cities and the county reported 535 ADUs finished (certificate of occupancy) in 2025, up from 165 in 2020.
- Another 1,378 approved ADU projects have no building permit reported yet, led by Oxnard (473) and Unincorporated Ventura County (455).
- Median time from application to permit ranged from 58 days in Ojai to 428 days in Oxnard (its times include planning review).
- Outside the cities, the most active communities are Meiners Oaks, Mira Monte and Oak View.
ADU permits reported in Ventura County, by year
| Year | Permits reported | ADUs finished |
|---|---|---|
| 2018 | 149 | 42 |
| 2019 | 152 | 95 |
| 2020 | 275 | 165 |
| 2021 | 273 | 125 |
| 2022 | 580 | 311 |
| 2023 | 665 | 397 |
| 2024 | 688 | 406 |
| 2025 | 923 | 535 |
Part of the rise reflects more complete reporting: some cities' early reports left out permits (see “About this data”). “Finished” counts units with a certificate of occupancy that year.
By city and area
| Area | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | Total | Approved, no permit yet | Median days to permit |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Oxnard | 3 | 14 | 31 | 95 | 119 | 192 | 197 | 237 | 888 | 473 | 428* |
| Thousand Oaks | 19 | 20 | 40 | 68 | 133 | 116 | 73 | 117 | 586 | 307 | 146 |
| Simi Valley | 27 | 24 | 52 | 24 | 72 | 83 | 92 | 192 | 566 | 26 | 211 |
| Unincorporated Ventura County | 62 | 46 | 60 | 30 | 74 | 117 | 75 | 101 | 565 | 455 | 221 |
| Ventura | 1 | 12 | 11 | 1 | 47 | 35 | 131 | 163 | 401 | 1 | — |
| Ojai | 22 | 19 | 33 | 5 | 42 | 26 | 43 | 32 | 222 | 26 | 58 |
| Camarillo | 9 | 7 | 13 | 12 | 36 | 49 | 41 | 35 | 202 | 60 | 80 |
| Moorpark | 6 | 7 | 30 | 27 | 17 | 12 | 15 | 26 | 140 | 3 | 80 |
| Port Hueneme | 0 | 3 | 2 | 7 | 12 | 23 | 15 | 13 | 75 | 12 | 36 |
| Fillmore | 0 | 0 | 3 | 4 | 12 | 12 | 6 | 7 | 44 | 0 | — |
| Santa Paula | 0 | 0 | 0 | 0 | 16 | 0 | 0 | 0 | 16 | 15 | — |
* Includes planning review: these cities report their planning application date to the state.
Each project is counted once, in its building-permit year. Approved projects and median days cover the same years. Median days use the application date each city reported, where it did. Each area links to its full page.
About this data
- Source: California Department of Housing and Community Development, Housing Element Annual Progress Reports (data.ca.gov), which every city and county files each year. They report ADU permits and completions, but not ADU type or cost.
- Fillmore's state reports include no ADUs before 2020.
- Ojai reported far fewer ADUs for 2021 than for the years around it, and for 2024 mostly completed projects (counted in their completion year); those years likely understate permit activity.
- Oxnard reports its planning case numbers and planning application dates to the state, so its timelines run from the planning application to the building permit and are longer than building review alone.
- Santa Paula reported no ADU building-permit dates. Its 2022 figures count completed projects; for 2021, 2023 and 2024 it reported only approvals, which are listed separately. Counts likely understate activity.
- Simi Valley reported no ADU building-permit dates for 2019 and, for 2020–2024, appears to have reported only completed projects; those are counted in their completion year. Yearly counts likely understate permit activity.
- Ventura reported no ADU building-permit dates for 2023; that year's bar counts completions only and is likely incomplete.
- Unincorporated Ventura County covers the parts of the county outside any city, such as Oak Park, Somis, Meiners Oaks, Oak View and Santa Rosa Valley. The county reports them together; its page breaks them down by community using each permit's location (Census designated places), with rural areas counted separately.
- Public-record permit data only — not zoning, feasibility, or legal advice. Records may be incomplete, delayed, or mis-categorized. Check with your city planning department.
Reporters: the figures are free to cite and reuse with credit and a link to this page, under CC BY 4.0. Questions: [email protected].