California ADU Regulations
California law sets a floor every city must meet: most single-family lots can have up to three units (an ADU, a junior ADU, and a new detached ADU), and cities must approve compliant plans within 60 days. Cities can be more generous, but not stricter.
Select your city below for verified local regulations, permit timelines, and costs.
California ADU Law at a Glance
Last reviewed September 30, 2026
- Units per lot
- Single-family lots can have one ADU converted from existing space, one JADU, and one new detached ADU (up to 800 sq ft). Multifamily lots can add up to 8 detached ADUs (never more than the number of existing units) plus conversions for up to 25% of existing units. Gov. Code §66323; SB 1211 (2024)
- Size
- Cities must allow at least an 800 sq ft ADU with 4 ft side and rear setbacks. Local maximums can be no lower than 850 sq ft (studio or one bedroom) or 1,000 sq ft (two or more bedrooms). JADUs are capped at 500 sq ft of interior livable space. Gov. Code §§66321, 66333
- Height
- Detached ADUs: at least 16 ft; 18 ft within half a mile of major transit (plus 2 ft to match the roof pitch of the main home) or on a lot with a multistory multifamily building. Attached ADUs: 25 ft or the zone height limit, whichever is lower. Gov. Code §66321(b)(4); AB 2221 and SB 897 (2022)
- Setbacks
- Side and rear setbacks for new ADUs can be no more than 4 ft. Conversions of existing legal structures need no extra setback. Front setbacks cannot block an 800 sq ft ADU. Gov. Code §66314(d)(7); AB 2221 (2022)
- Permit timeline
- The city has 15 business days to say whether an application is complete, or it is deemed complete. It must then approve or deny a complete application within 60 days, with no public hearing. Gov. Code §66317; SB 543 (2025)
- Impact fees
- No impact fees on ADUs under 750 sq ft; larger units pay fees proportional to the main home. ADUs and JADUs of 500 sq ft or less are exempt from school impact fees. Gov. Code §66324; SB 543 (2025)
- Owner-occupancy
- Cities cannot require the owner to live on site for an ADU. For a JADU, owner-occupancy can be required only if the JADU shares a bathroom with the main home. JADUs cannot be short-term rentals. AB 976 (2023); AB 1154 (2025)
- Parking
- No parking is required for an ADU within half a mile walk of public transit, in a historic district, or for a conversion, and garage parking lost to an ADU does not have to be replaced. Gov. Code §66322
Data & Reports
Compare All 100 Cities
Sortable table: max size, setbacks, fees, and build costs for every California city.
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State of ADU in California 2026
Annual report: average costs, permit fees, rental income, and regulatory trends across 100 cities.
Read report →
ADU Cost Index 2026
Build costs ranked from lowest to highest, broken down by city and county. Updated quarterly.
View index →
Browse by City
Find Your City
Los Angeles
Los Angeles County
Max: 1,200 sq ft
Cost: $150,000 – $450,000
San Diego
San Diego County
Max: 1,200 sq ft
Cost: $160,000 – $480,000
San Jose
Santa Clara County
Max: 1,200 sq ft
Cost: $200,000 – $550,000
San Francisco
San Francisco County
Max: 1,000 sq ft
Cost: $250,000 – $700,000
Fresno
Fresno County
Max: 1,200 sq ft
Cost: $90,000 – $200,000
Sacramento
Sacramento County
Max: 1,200 sq ft
Cost: $130,000 – $380,000
Long Beach
Los Angeles County
Max: 1,200 sq ft
Cost: $150,000 – $420,000
Oakland
Alameda County
Max: 1,000 sq ft
Cost: $200,000 – $550,000
Bakersfield
Kern County
Max: 1,200 sq ft
Cost: $85,000 – $190,000
Anaheim
Orange County
Max: 1,200 sq ft
Cost: $140,000 – $300,000
Stockton
San Joaquin County
Max: 1,200 sq ft
Cost: $90,000 – $200,000
Riverside
Riverside County
Max: 1,200 sq ft
Cost: $110,000 – $240,000
Santa Ana
Orange County
Max: 1,000 sq ft
Cost: $120,000 – $260,000
Irvine
Orange County
Max: 1,200 sq ft
Cost: $160,000 – $340,000
Chula Vista
San Diego County
Max: 1,200 sq ft
Cost: $140,000 – $300,000
Fremont
Alameda County
Max: 1,200 sq ft
Cost: $200,000 – $420,000
Santa Clarita
Los Angeles County
Max: 1,000 sq ft
Cost: $150,000 – $320,000
San Bernardino
San Bernardino County
Max: 1,200 sq ft
Cost: $100,000 – $220,000
Modesto
Stanislaus County
Max: 1,000 sq ft
Cost: $90,000 – $195,000
Fontana
San Bernardino County
Max: 1,200 sq ft
Cost: $110,000 – $230,000
Oxnard
Ventura County
Max: 1,200 sq ft
Cost: $150,000 – $320,000
Moreno Valley
Riverside County
Max: 1,200 sq ft
Cost: $110,000 – $230,000
Huntington Beach
Orange County
Max: 1,200 sq ft
Cost: $175,000 – $380,000
Glendale
Los Angeles County
Max: 1,000 sq ft
Cost: $160,000 – $370,000
Ontario
San Bernardino County
Max: 1,000 sq ft
Cost: $115,000 – $240,000
Elk Grove
Sacramento County
Max: 1,200 sq ft
Cost: $120,000 – $260,000
Santa Rosa
Sonoma County
Max: 1,200 sq ft
Cost: $170,000 – $360,000
Rancho Cucamonga
San Bernardino County
Max: 1,200 sq ft
Cost: $150,000 – $310,000
Palmdale
Los Angeles County
Max: 1,200 sq ft
Cost: $130,000 – $270,000
Garden Grove
Orange County
Max: 1,200 sq ft
Cost: $160,000 – $330,000
Oceanside
San Diego County
Max: 1,200 sq ft
Cost: $160,000 – $330,000
Corona
Riverside County
Max: 1,200 sq ft
Cost: $145,000 – $300,000
Lancaster
Los Angeles County
Max: 1,200 sq ft
Cost: $120,000 – $250,000
Salinas
Monterey County
Max: 1,200 sq ft
Cost: $155,000 – $310,000
Hayward
Alameda County
Max: 1,200 sq ft
Cost: $185,000 – $380,000
Sunnyvale
Santa Clara County
Max: 1,200 sq ft
Cost: $220,000 – $430,000
Pomona
Los Angeles County
Max: 1,200 sq ft
Cost: $140,000 – $290,000
Escondido
San Diego County
Max: 1,200 sq ft
Cost: $155,000 – $320,000
Torrance
Los Angeles County
Max: 1,200 sq ft
Cost: $175,000 – $360,000
Roseville
Placer County
Max: 1,000 sq ft
Cost: $155,000 – $310,000
Orange
Orange County
Max: 1,000 sq ft
Cost: $165,000 – $340,000
Fullerton
Orange County
Max: 1,200 sq ft
Cost: $160,000 – $330,000
Visalia
Tulare County
Max: 1,200 sq ft
Cost: $120,000 – $250,000
Pasadena
Los Angeles County
Max: 1,200 sq ft
Cost: $170,000 – $480,000
Thousand Oaks
Ventura County
Max: 1,000 sq ft
Cost: $150,000 – $400,000
Simi Valley
Ventura County
Max: 1,200 sq ft
Cost: $155,000 – $310,000
Concord
Contra Costa County
Max: 1,200 sq ft
Cost: $170,000 – $340,000
Santa Clara
Santa Clara County
Max: 1,200 sq ft
Cost: $220,000 – $430,000
Victorville
San Bernardino County
Max: 1,000 sq ft
Cost: $115,000 – $240,000
Vallejo
Solano County
Max: 1,200 sq ft
Cost: $155,000 – $310,000
Berkeley
Alameda County
Max: 1,200 sq ft
Cost: $230,000 – $450,000
Fairfield
Solano County
Max: 1,200 sq ft
Cost: $145,000 – $295,000
Clovis
Fresno County
Max: 1,200 sq ft
Cost: $120,000 – $250,000
Murrieta
Riverside County
Max: 1,200 sq ft
Cost: $145,000 – $295,000
El Monte
Los Angeles County
Max: 1,000 sq ft
Cost: $145,000 – $295,000
Downey
Los Angeles County
Max: 1,000 sq ft
Cost: $150,000 – $310,000
Carlsbad
San Diego County
Max: 1,200 sq ft
Cost: $175,000 – $360,000
Antioch
Contra Costa County
Max: 1,200 sq ft
Cost: $150,000 – $305,000
Temecula
Riverside County
Max: 1,200 sq ft
Cost: $150,000 – $305,000
Costa Mesa
Orange County
Max: 1,200 sq ft
Cost: $175,000 – $360,000
Richmond
Contra Costa County
Max: 1,000 sq ft
Cost: $160,000 – $330,000
Jurupa Valley
Riverside County
Max: 1,000 sq ft
Cost: $130,000 – $270,000
Ventura
Ventura County
Max: 1,000 sq ft
Cost: $160,000 – $325,000
Chico
Butte County
Max: 1,200 sq ft
Cost: $130,000 – $265,000
Inglewood
Los Angeles County
Max: 1,000 sq ft
Cost: $160,000 – $330,000
West Covina
Los Angeles County
Max: 1,000 sq ft
Cost: $150,000 – $305,000
Norwalk
Los Angeles County
Max: 1,000 sq ft
Cost: $150,000 – $305,000
Burbank
Los Angeles County
Max: 1,000 sq ft
Cost: $175,000 – $360,000
Daly City
San Mateo County
Max: 1,200 sq ft
Cost: $210,000 – $420,000
Santa Maria
Santa Barbara County
Max: 1,200 sq ft
Cost: $135,000 – $275,000
San Mateo
San Mateo County
Max: 1,200 sq ft
Cost: $220,000 – $430,000
El Cajon
San Diego County
Max: 1,200 sq ft
Cost: $150,000 – $305,000
Rialto
San Bernardino County
Max: 1,200 sq ft
Cost: $130,000 – $265,000
Vacaville
Solano County
Max: 1,200 sq ft
Cost: $140,000 – $285,000
South Gate
Los Angeles County
Max: 1,000 sq ft
Cost: $145,000 – $295,000
Menifee
Riverside County
Max: 1,500 sq ft
Cost: $135,000 – $275,000
Tracy
San Joaquin County
Max: 1,200 sq ft
Cost: $130,000 – $265,000
Vista
San Diego County
Max: 1,200 sq ft
Cost: $150,000 – $305,000
Compton
Los Angeles County
Max: 1,200 sq ft
Cost: $145,000 – $290,000
Mission Viejo
Orange County
Max: 1,200 sq ft
Cost: $165,000 – $335,000
Hesperia
San Bernardino County
Max: 1,200 sq ft
Cost: $115,000 – $235,000
Redding
Shasta County
Max: 1,000 sq ft
Cost: $120,000 – $245,000
Santa Monica
Los Angeles County
Max: 1,200 sq ft
Cost: $200,000 – $600,000
Santa Barbara
Santa Barbara County
Max: 1,200 sq ft
Cost: $200,000 – $400,000
San Leandro
Alameda County
Max: 1,200 sq ft
Cost: $175,000 – $360,000
Livermore
Alameda County
Max: 1,200 sq ft
Cost: $180,000 – $365,000
Westminster
Orange County
Max: 1,200 sq ft
Cost: $165,000 – $335,000
Citrus Heights
Sacramento County
Max: 1,200 sq ft
Cost: $140,000 – $285,000
Hawthorne
Los Angeles County
Max: 1,000 sq ft
Cost: $160,000 – $330,000
Whittier
Los Angeles County
Max: 1,200 sq ft
Cost: $155,000 – $315,000
Newport Beach
Orange County
Max: 1,200 sq ft
Cost: $200,000 – $410,000
Alhambra
Los Angeles County
Max: 1,200 sq ft
Cost: $155,000 – $315,000
Lake Forest
Orange County
Max: 1,000 sq ft
Cost: $165,000 – $335,000
Hemet
Riverside County
Max: 1,200 sq ft
Cost: $110,000 – $225,000
Napa
Napa County
Max: 1,200 sq ft
Cost: $175,000 – $355,000
Lodi
San Joaquin County
Max: 1,000 sq ft
Cost: $120,000 – $245,000
Santa Cruz
Santa Cruz County
Max: 1,200 sq ft
Cost: $195,000 – $395,000
Petaluma
Sonoma County
Max: 1,000 sq ft
Cost: $165,000 – $330,000
San Luis Obispo
San Luis Obispo County
Max: 1,000 sq ft
Cost: $170,000 – $345,000
Palm Springs
Riverside County
Max: 1,000 sq ft
Cost: $155,000 – $315,000
Browse by County