CostolioADU (accessory dwelling unit) cost by city
Compare ADU cost across California cities using public building permits. Building a new accessory dwelling unit, or converting a garage or other space into one.
Adu cost by city
| City | Median | Middle half | Permits | Dates | Source | Checked on |
|---|---|---|---|---|---|---|
| Los Angeles | $65,000 | $35,000 to $120,000 | 33285 | 2022-01-01 to 2026-10-31 | Building and Safety - Building Permits Issued from 2020 to Present (N) | 2026-11-02 |
| Richmond | $97,000 | $64,750 to $140,000 | 191 | 2022-01-05 to 2025-04-22 | PermitTrak | 2026-11-02 |
| San Diego | $118,620 | $67,720 to $194,828 | 5585 | 2022-01-03 to 2026-10-30 | Development Permits - approvals issued (set 1) | 2026-11-02 |
What a adu (accessory dwelling unit) permit usually covers
Usually the new unit's structure, foundation, framing, plumbing, electrical and mechanical work the city inspects. Site work, utility connection fees, design fees, appliances and furnishings are often priced or listed separately.
Read this first. Permit values are self-reported by the applicant to set permit fees. They often leave out materials or labor, and they are not what the contractor actually charged. A quote above or below this range can be reasonable.
Updated