California / ADU builders

ADU builders in California, by city

The short answer

794 licensed contractors building accessory dwelling units across 21 California cities, with 520 ADU permits on file between them. Every licence is checked against the California state register. Order is set by public records, never by payment.

California Contractors State License Board, checked 2026-08-15

How to read this. Licence details come from the California Contractors State License Board and are dated on each profile. Permit counts reflect only those cities that publish the contractor's name on a building permit, so a builder with none listed may simply have worked where nothing is published. A city that pre-approves a plan has vetted the plan, not the builder, and does not endorse it. ADU Standards takes no payment for placement. Confirm any licence at cslb.ca.gov before you sign.

Pick a city

Coverage

City	County	Builders	ADU permits on file	Pre-approved plans
San Jose	Santa Clara	249	333	4
Los Gatos	Santa Clara	128	159	none
Danville	Contra Costa	44	not published	none
Walnut Creek	Contra Costa	34	not published	none
Santa Clara	Santa Clara	33	not published	2
Sunnyvale	Santa Clara	33	not published	4
Mountain View	Santa Clara	28	not published	none
Saratoga	Santa Clara	25	28	none
Fremont	Alameda	24	not published	3
Concord	Contra Costa	23	not published	none
Los Angeles	Los Angeles	23	not published	11
Berkeley	Alameda	20	not published	3
Oakland	Alameda	19	not published	none
San Diego	San Diego	17	not published	none
San Ramon	Contra Costa	17	not published	none
Campbell	Santa Clara	15	not published	none
San Mateo	San Mateo	15	not published	none
Santa Monica	Los Angeles	13	not published	none
Palo Alto	Santa Clara	12	not published	none
Sacramento	Sacramento	12	not published	none
Pasadena	Los Angeles	10	not published	none

Common questions

How are these ADU builder lists put together?

Every company is matched to an active licence with the California Contractors State License Board before it appears. Order is set by what public records confirm: ADU permits on file in that city, whether the city has pre-approved the company’s plans, and licence standing. No builder pays for position and none can request removal.

Does ADU Standards take money from builders?

Not for placement. A builder may pay for a lead once a homeowner asks to be contacted, but nothing a builder pays for affects the order of any list or whether a company appears on it. Ordering is computed from public records only.

Which California cities are covered?

Builder lists currently cover 21 cities. ADU rules, ordinance compliance status and statutory citations cover every California jurisdiction, because the state floor applies to all of them by operation of law.