The short answer
Median time from application to issued ADU permit ranges from 58 days in Ojai to 428 days in Oxnard (which includes planning review), among areas with at least 50 timed permits, based on the dates each city and the county report to the state.
| City or area | Median days, application to permit | Permits timed |
|---|---|---|
| Camarillo | 80 | 104 |
| Moorpark | 80 | 76 |
| Ojai | 58 | 67 |
| Oxnard | 428* | 259 |
| Port Hueneme | 36 | 16 |
| Simi Valley | 211 | 80 |
| Thousand Oaks | 146 | 266 |
| Unincorporated Ventura County | 221 | 53 |
* This city reports its planning application date, so its time includes planning review.
Cities not listed don't report enough application dates to time permits.
What about the state's 60-day rule?
California law requires a city or county to approve or deny a complete ADU application within 60 days (Government Code § 66317, summarized in the state's ADU Handbook). The times above start when an application was first submitted, so they also include corrections, resubmittals and fees, which is why most run longer.
Approved, but no building permit yet
Across Ventura County, 1,378 ADU projects approved from 2018 through 2025 had no building permit reported, led by Oxnard (473), Unincorporated Ventura County (455) and Thousand Oaks (307). Some cities approve an ADU in planning before the building permit, so a project can wait between the two.
After the permit
Ventura County's cities and the county reported 535 ADUs finished (certificate of occupancy) in 2025. See how long ADUs take to build and the Ventura County ADU report.
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