Bay Area, CA · Updated 2026
Bay Area ADU Permits: Fees, Timeline & Process
San Francisco, San Jose, and surrounding cities — California's 60-day shot clock and pre-approved plans.
Quick Answer
Bay Area ADUs: $175K–$500K
Permits: $15K–$50K · Updated April 2026
Bay Area ADU Permitting: Overview
The Bay Area has some of the highest ADU permit fees in the country, but also some of the strongest state-level protections for homeowners. California's 60-day shot clock, impact fee waivers for units under 750 sq ft, and mandatory pre-approved plan programs all apply across San Francisco, San Jose, Oakland, and surrounding jurisdictions.
Permit costs and timelines vary significantly by city. San Francisco's DBI charges $15,000–$30,000 in permit and plan review fees, while San Jose charges approximately $17,265 for a 751–1,200 sq ft attached ADU. Most Bay Area cities now qualify for ministerial (non-discretionary) ADU approval, meaning projects that meet zoning standards cannot be denied.
Permit Fees Breakdown
Total permitting costs in Bay Area typically range from $15,000–$50,000 depending on ADU type, size, and site conditions.
| Fee Type | Amount | Notes |
|---|---|---|
| Building Permit (SF) | $5,000–$15,000 | Based on valuation; $308/hr plan review |
| Building Permit (SJ) | $2,670–$17,265 | Varies by ADU type and size |
| Plan Review | $3,000–$10,000 | Varies by jurisdiction |
| Impact Fees (< 750 sf) | Waived | California state law exemption |
| Impact Fees (750+ sf) | $10,000+ | Proportional to unit size |
| Utility Connections | $5,000–$15,000 | Water, sewer, electrical |
| School Fees | $2–$4/sq ft | Varies by district |
| Energy Compliance | $500–$2,000 | Title 24 and CALGreen review |
Fees are estimates based on typical ADU projects. Contact Bay Area permitting for exact quotes. See our full permit fees guide for comparison across cities.
Zoning & Requirements
- ADUs allowed on any residential lot in California (state law)
- No minimum lot size required
- Detached ADU max: 1,200 sq ft; Attached max: 50% of primary dwelling up to 1,200 sq ft
- JADU max: 500 sq ft (within existing structure)
- Height: 16–25 feet depending on zone and transit proximity
- Setbacks: 4 feet rear/side for detached ADUs
- No parking required within half mile of transit
- No owner-occupancy for standard ADUs
- Impact fees waived for ADUs under 750 sq ft
Step-by-Step Permit Process
Confirm eligibility
Check your city's zoning map. Most single-family lots in the Bay Area qualify. Contact your local planning department for a free pre-application consultation.
Choose plan type
Select from your city's pre-approved ADU plans (required by AB 1332) or hire an architect for custom designs. Pre-approved plans get 30-day review in many cities.
Prepare documents
Site plan, floor plans, elevations, structural calculations, Title 24 energy calcs, and CALGreen compliance checklist.
Submit application
Most Bay Area cities accept online submissions. San Francisco uses DBI's permit portal; San Jose uses the Development Services portal.
60-day review clock starts
California law requires cities to approve or deny complete ADU applications within 60 days. SB 543 requires completeness confirmation within 15 business days.
Address corrections
Respond to plan check comments promptly. AB 253 allows you to hire a private plan checker if the city takes more than 30 business days.
Pay fees & receive permit
Pay remaining permit fees, impact fees (if applicable), and utility connection charges.
Construction & inspections
Schedule inspections at each phase. Bay Area cities typically offer same-day or next-day inspections.
Key Regulations & Laws
60-Day Shot Clock
California law requires cities to approve or deny complete ADU applications within 60 days. This applies to all Bay Area jurisdictions.
SB 543 (2025)
Cities must confirm application completeness within 15 business days and cannot add new requirements after resubmission.
AB 1332 Pre-Approved Plans
All California cities must offer pre-approved ADU plan programs, cutting design costs and review time.
AB 253 Private Plan Check
If your city takes more than 30 business days, you can hire a private plan checker at the city's expense.
Impact Fee Waiver
ADUs under 750 sq ft are exempt from development impact fees statewide.
Frequently Asked Questions
How much do ADU permits cost in the Bay Area?
Permit costs vary by city: San Francisco charges $15,000–$30,000 total, San Jose around $2,670–$17,265 depending on size, and smaller cities like San Mateo charge $2,671 for a new ADU building permit. Impact fees are waived for ADUs under 750 sq ft.
How long does ADU permitting take in San Francisco?
San Francisco DBI processes most qualifying ADU applications in 6–9 months, down from 12+ months in prior years. Pre-approved plans can be faster. California's 60-day shot clock applies but is measured from completeness determination.
Do I need to pay impact fees for my ADU?
Not if your ADU is under 750 square feet — California law waives development impact fees for smaller ADUs. For larger units, fees are proportional to the ADU's size relative to the primary dwelling.
Can I sell my ADU separately from my main house?
AB 1033 gives cities the option to allow separate ADU sales through condominium mapping. Check whether your specific city has adopted this option.
Your Next Steps
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