Contra Costa County, CA Short-Term Rentals: Registration Rules (2026)

Unincorporated Contra Costa County regulates short-term rentals (stays under 30 days) primarily through its Transient Occupancy Tax ordinance (County Ordinance Code Chapter 64-10). Any operator of transient lodging, including vacation rentals booked through Airbnb, Vrbo, or directly, must register with the Treasurer-Tax Collector within 30 days of starting operations and obtain a Transient Occupancy Registration Certificate. The county does not operate a separate STR-specific permit program equivalent to what some cities have, but STR operators must also obtain a business license. Zoning compliance is required: STRs are only allowed in residential zones where such use is not otherwise restricted, and some residential zones or specific community plan areas (e.g., Discovery Bay, Bay Point) may impose additional requirements. Airbnb has a direct collection agreement with Contra Costa County, meaning the platform collects and remits TOT automatically on qualifying bookings, but operators must still register and obtain a certificate. Failure to register or remit TOT results in penalties and interest.