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 AngelesCalifornia | San FranciscoCalifornia | |
|---|---|---|
| ADUs Allowed? | Yes, by right in all residential zones | Yes, by right in all residential zones |
| Max Detached ADU Size | 1,200 sq ft | 1,200 sq ft |
| Max Attached ADU Size | 1,200 sq ft or 50% of primary | 1,200 sq ft or 50% of primary |
| 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
ADU construction in Los Angeles typically costs $150,000-$350,000, while San Francisco ranges from $200,000-$500,000. The difference is driven primarily by labor costs and local fee structures.
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. View source