While California state law sets baseline ADU requirements, each city implements regulations differently. Understanding your specific city's requirements, timeline, and processes is essential for efficient permit approval. This guide covers the major California cities where we process the most ADU permits.
State Law is the Floor: Cities cannot impose requirements more restrictive than state law, but they can be more permissive. If your city's rules conflict with state law, state law prevails.
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Los Angeles
Los Angeles is California's ADU capital, issuing more permits than any other city. LADBS (Los Angeles Department of Building and Safety) has streamlined their process with free pre-approved standard plans and dedicated ADU counters.
Key Requirements
- Zoning: ADUs allowed in all residential zones (R1, R2, R3, R4, R5)
- Size limits: Up to 1,200 sq ft detached; attached limited to 50% of primary dwelling or 1,200 sq ft
- Setbacks: 4 feet side and rear (state minimum)
- Height: 16 feet (detached), 18 feet for ADU over garage
- Lot coverage: Must leave 25% open space, but guaranteed 800 sq ft ADU minimum
- Parking: None required (citywide exemption)
Cost Breakdown
- Building permit: $3,000-$8,000
- Plan check: $1,500-$4,000
- School fees: $3-$4/sq ft ($2,400-$4,800)
- Professional soft costs: $8,000-$18,000
Pro Tip: Use LADBS's free pre-approved standard plans to cut design costs and approval time by 30-50%. Plans available at ladbs.org/adu.
Website: ladbs.org/adu
Phone: (213) 482-6800
Walk-in: Multiple permit centers citywide
San Francisco
San Francisco has California's highest permit fees (6-9% of construction cost) but offers 100% electronic review through their SF Planning portal. The city is space-constrained, making garage conversions and rear-yard ADUs popular.
Key Requirements
- Permit type: Over-the-counter for simple projects; full plan check for complex
- Size limits: 1,200 sq ft maximum
- Setbacks: 4 feet (state minimum); existing structures exempt
- Height: Varies by district; typically 16-18 feet for detached
- Fire sprinklers: Often required due to density
- School fees: Waived for ADUs
Cost Breakdown
- Building permit: $12,000-$20,000 (6-9% of construction)
- Plan check: $8,000-$14,000
- Professional soft costs: $12,000-$20,000
- School fees: Waived
Pro Tip: Submit early in the week (Monday-Tuesday) to get assigned to plan checkers faster. Use the DBI appointment system for complex questions.
San Diego
San Diego has a well-organized ADU program with clear requirements. The key consideration is whether your property is in the Coastal Overlay Zone, which requires additional Coastal Development Permits and extends timelines significantly.
Key Requirements
- Companion unit program: San Diego's term for ADUs
- Size limits: 1,200 sq ft maximum
- Setbacks: 4 feet side and rear
- Height: 16 feet (single story), 18 feet over garage
- Coastal properties: Require Coastal Development Permit (CDP)
- Parking: None required in most areas
Coastal Zone Considerations
- CDP adds $2,000-$8,000 in permit costs
- Review time: 60-120 additional days
- May require Coastal Commission approval for some projects
- AB 462 (2026) streamlines coastal ADU approvals
Pro Tip: Check if your property is in the Coastal Overlay Zone using SD's zoning map BEFORE starting design. This affects your entire permit strategy.
Website: sandiego.gov/development-services/adu
Phone: (619) 446-5000
ADU Info Line: (619) 446-5200
San Jose
San Jose consistently achieves some of California's fastest ADU permit timelines. Their digital review system and ADU-friendly policies make it one of the easiest cities for permit approval.
Key Requirements
- Zones: Allowed in all residential zones
- Size limits: 1,200 sq ft or 50% of primary dwelling for attached
- Setbacks: 4 feet side and rear
- Height: 16 feet (detached), varies for attached
- Pre-approved plans: Available for faster processing
- Electronic submittal: Required for all permits
What Makes San Jose Fast
- Dedicated ADU review team
- Clear, consistent interpretation of codes
- Efficient digital workflow
- Proactive communication on corrections
Pro Tip: San Jose's pre-approved ADU plans can cut weeks off your timeline. Even with custom designs, their review is among the fastest in California.
Website: sanjoseca.gov/adu
Phone: (408) 535-3555
Virtual Counter: Available for questions
We Know Your City's Requirements
Our team has submitted permits in all these cities and knows exactly what each one requires. Get plans designed to pass on first review.
Get City-Specific PlanningSacramento
Sacramento has actively promoted ADU development as part of its housing strategy. The city offers competitive permit fees and reasonable timelines, making it an attractive market for ADU development.
Key Requirements
- Zones: All residential zones plus mixed-use
- Size limits: 1,200 sq ft for detached; 50% or 1,200 for attached
- Setbacks: 4 feet (matching state law)
- Height: 16 feet detached, matching primary for attached
- Parking: None required citywide
- JADUs: Allowed up to 500 sq ft
Sacramento ADU Program
- Pre-application meetings available and recommended
- Standard plan sets offered
- Fee deferral programs available
- ADU financing assistance programs
Pro Tip: Take advantage of Sacramento's pre-application meeting program. It's free and helps identify potential issues before you spend money on design.
Website: cityofsacramento.org/adu
Phone: (916) 808-5311
Permit Center: 300 Richards Blvd
Oakland
Oakland has embraced ADU development with over-the-counter permits for qualifying projects and pre-approved plans. The city offers some of the Bay Area's most reasonable permit costs.
Key Requirements
- Over-the-counter: Available for simple ADUs using pre-approved plans
- Size limits: 1,200 sq ft maximum
- Setbacks: 4 feet side and rear
- Height: 16-18 feet depending on configuration
- Fire zones: Additional requirements in hills
- Seismic: Standard Bay Area seismic requirements
Over-the-Counter Requirements
- Must use Oakland pre-approved ADU plan
- Single-story detached only
- Standard foundation (not hillside)
- No variances or exceptions needed
Pro Tip: If your property qualifies, Oakland's over-the-counter process can get you a permit the same day. This requires using pre-approved plans and meeting specific criteria.
Website: oaklandca.gov/topics/adu
Phone: (510) 238-3891
Permit Center: 250 Frank H. Ogawa Plaza
Long Beach
Long Beach has an established ADU program with reasonable fees and good communication. The city distinguishes between ADUs and "accessory living quarters" (similar to JADUs).
Key Requirements
- Zones: All residential zones
- Size limits: 1,200 sq ft detached; attached varies
- Setbacks: 4 feet (state minimum)
- Height: 16 feet detached
- Coastal properties: Subject to Local Coastal Program
- Historic districts: May require design review
Pro Tip: Long Beach has excellent online resources and responsive staff. Their pre-application consultation is valuable for complex sites.
Website: longbeach.gov/lbds/adu
Phone: (562) 570-6194
Permit Center: 411 W. Ocean Blvd
Fresno
Fresno offers some of California's most affordable ADU permit costs and fastest timelines. The Central Valley city has embraced ADU development as a housing solution.
Key Requirements
- Zones: All residential zones
- Size limits: 1,200 sq ft maximum
- Setbacks: 4 feet side and rear
- Height: 16 feet for detached ADUs
- Parking: None required
- Lot size: No minimum beyond primary dwelling requirements
Why Fresno is Affordable
- Lower permit fees than coastal cities
- Competitive professional service costs
- Lower construction costs (labor, materials)
- Efficient review process
Pro Tip: Fresno's affordable permit costs make it an excellent market for ADU investment properties. ROI calculations often favor Central Valley locations.
Website: fresno.gov/darm
Phone: (559) 621-8277
Permit Center: 2600 Fresno Street
Quick Comparison
| City | Permit Costs | Timeline | Pre-Approved Plans | Key Consideration |
|---|---|---|---|---|
| Los Angeles | $15K-$35K | 50-120 days | 20+ free plans | Highest volume; use standard plans |
| San Francisco | $33K-$57K | 90-150 days | Limited | Highest fees; electronic review |
| San Diego | $15K-$35K | 50-180 days | Available | Coastal zone adds complexity |
| San Jose | $22K-$45K | 35-55 days | Yes | Fastest approvals |
| Sacramento | $14K-$28K | 45-70 days | Yes | Good balance of cost/speed |
| Oakland | $18K-$38K | 55-80 days | Yes (OTC) | Same-day OTC option |
| Long Beach | $16K-$32K | 45-75 days | Limited | Established program |
| Fresno | $10K-$20K | 40-60 days | Limited | Lowest costs statewide |
Not Sure About Your City?
We serve all California cities and know the specific requirements for each. Get expert guidance for your location.
Schedule Your Free ConsultationDisclaimer: City requirements, fees, and timelines change frequently. The information in this guide reflects typical 2026 conditions and should be verified with your local building department before relying on it for planning purposes. This guide does not constitute legal advice.