ADU Rules: Los Angeles vs San Francisco (2026 Comparison)
Compare ADU regulations, permit fees, size limits, and timelines between Los Angeles and San Francisco. Which city is more ADU-friendly?
Side-by-Side Comparison
Los Angeles vs San Francisco
| Los AngelesCA | San FranciscoCA | |
|---|---|---|
| ADUs Allowed? | Yes, by right in all residential zones | Yes, by right in all residential zones |
| Max Detached ADU Size | 1,200 sq ft | 1,000 sq ft (SF Planning Code §207.2) |
| Max Attached ADU Size | 1,200 sq ft or 50% of primary | 50% of primary or 850–1,000 sq ft, whichever is greater (SF Planning Code §207) |
| Estimated Permit Fees | $5,000 - $15,000 | $8,000 - $25,000 |
| Permit Timeline | 6-12 months | 8-14 months |
| Owner Occupancy Required? | No (state law prohibits) | No (state law prohibits) |
| Parking Required? | No (state law waiver) | No (state law waiver) |
| State Preemption? | Yes (CA state law) | Yes (CA state law) |
Key Differences
While both Los Angeles and San Francisco operate under the same California state ADU laws, the permit process and costs differ significantly. San Francisco's higher construction costs and more complex permitting process make ADU development notably more expensive. Los Angeles has streamlined its ADU permitting in recent years with standardized plans that can reduce approval times.
Cost Comparison
Los Angeles permit fees typically run $5,000–$15,000; San Francisco $8,000–$25,000 based on published fee schedules. ADU construction costs vary significantly by design, materials, and contractor — see your city's fee schedule for current official amounts. For Los Angeles fee information see LADBS (ladbs.org); for San Francisco see SFDBI (sfdbi.org).
Our Verdict
Los Angeles is the more ADU-friendly city for most homeowners. Lower costs, faster permitting, and a larger pool of experienced ADU builders give LA an edge. San Francisco's higher costs may be offset by higher rental income potential.
Explore Each City
Frequently Asked Questions
Which city has cheaper ADU permits?
Los Angeles has lower permit fees, typically $5,000-$15,000 compared to San Francisco's $8,000-$25,000.
Do both cities follow the same ADU laws?
Yes, both operate under California state ADU law which preempts local restrictions on setbacks, parking, and owner-occupancy requirements.
Source: PropertyZoned Editorial Research. Last verified April 3, 2026.