ADU Laws in California (2026)
California state ADU law details, key provisions, preemption status, and recent legislative changes for accessory dwelling units.
Law Name
California ADU Law (Government Code Section 65852.2)
Effective Date
2020-01-01
Preempts Local Ordinances
Yes — state law overrides local restrictions
Has State Law
Yes
Key Provisions
ADUs permitted by-right on all single-family and multifamily residential lots — no discretionary review allowed
JADUs (Junior ADUs) up to 500 sqft permitted within existing residential structures
Owner-occupancy requirement eliminated effective January 1, 2020
No setback requirement for ADU replacing existing structure in same footprint
4-foot side and rear setbacks for new detached ADUs
No minimum lot size for ADU development
Impact fees waived for ADUs under 750 sqft
School fees waived for ADUs under 750 sqft
Ministerial approval within 60 days required
ADUs cannot be sold separately from primary dwelling (except under SB 9 lot split)
Parking waived for ADUs within 0.5 miles of transit, in historic districts, or for garage conversions
Multifamily buildings may convert 25% of units to ADUs; at least 2 detached ADUs permitted per multifamily lot
Cities cannot require owner-occupied primary residence as condition of ADU approval
No requirement for ADU to match primary dwelling architecture in most cases
Legislative History
2019 — AB 68
Eliminated owner-occupancy requirement, reduced setbacks to 4 ft, eliminated minimum lot size requirement, streamlined approval to ministerial with 60-day deadline
2019 — AB 881
Prohibited cities from requiring ADU setbacks exceeding 4 ft rear/side, eliminated impact fees for ADUs under 750 sqft, expanded parking waivers
2021 — SB 9
Authorized urban lot splits on single-family parcels, allowing up to 4 units on lots that were previously single-family only. Ministerial approval required for qualifying splits.
2023 — AB 1033
Authorized local jurisdictions to optionally allow ADUs to be sold separately as condominiums from the primary dwelling unit
2024 — AB 2533
Further streamlined ADU permitting, clarified ministerial approval standards, strengthened local compliance requirements
Official Sources
What Does Preemption Mean for Local Cities?
Because California law preempts local ordinances, individual cities cannot impose restrictions stricter than the state standard. A city may still have additional administrative requirements, but cannot deny ADU applications that comply with state minimums.
Learn about Californiazoning preemption →Source: California ADU Law (Government Code Section 65852.2). Last verified April 3, 2026. View source