Rental Property Rules in Contra Costa County, CA (2026)

3 county-level rules, plus city-specific rules for 9 cities in Contra Costa County, California.

Verified from official government sources

Note: These county rules apply to unincorporated areas of Contra Costa County. If you live within an incorporated city, that city's own rules apply — see the city list below.

Rental Registration

Unincorporated Contra Costa County does not operate a mandatory rental registration program for single-family or small multi-family rentals. Landlords are subject to state requirements including AB 1482 rent cap, Tenant Protection Act, and general business tax filings.

Rental Property: Registration

Few Restrictions

AB 1482 / California Civil Code § 1947.12(a)-(b)

(a) (1) Subject to subdivision (b), an owner of residential real property shall not, over the course of any 12-month period, increase the gross rental rate for a dwelling or a unit more than 5 percent plus the percentage change in the cost of living, or 10 percent, whichever is lower, of the lowest gross rental rate charged for that dwelling or unit at any time during the 12 months prior to the...

Full ordinance details →Official source ↗

Lead Paint Disclosure

Federal Title X and California Health & Safety Code require lead paint disclosure for pre-1978 rental units in unincorporated Contra Costa County. Landlords must provide EPA pamphlet and disclosure form before lease signing.

Rental Property: Lead Paint Disclosure

Heavy Restrictions

EPA Guidance

Provide a "Lead Warning Statement" to buyers or renters explaining, among other things, that lead from paint can pose health hazards if not managed properly. This can be an attachment to or as language inserted into the contract or lease. This should be in the same language as the rest of the contract. It should include confirmation that the seller or landlord has complied with all requirements...

Full ordinance details →Official source ↗

Mold Disclosure

California Civil Code Section 1940.9 and Health & Safety Code Section 26147 require landlords to disclose known visible mold to prospective tenants. Contra Costa County follows state law with no supplemental local mold ordinance.