Contractors State License Board — California's regulatory body for construction contractors. Maintains a public database of licensed contractors searchable by license number, business name, or location.
The CSLB Instant License Check (cslb.ca.gov/onlineservices/checklicenseii) is the authoritative source for verifying any contractor's licence status, classifications, bond, and workers' comp coverage before signing. Our builder directory pulls from the CSLB Public Data Portal.
Part of the BackyardADU California ADU Glossary — plain-English definitions of the regulatory, construction, and financing terms you'll encounter during a California ADU project.