California contractor licensing: CSLB's A, B, B-2 and C classifications

Contractors in California are licensed by the Contractors State License Board (CSLB) under the Contractors' State License Law in the Business and Professions Code. The classification on a license controls the kind of work the holder may contract for. This guide summarizes the statute; check CSLB's current rules before you bid.

The main classifications

• Class A, general engineering (B&P § 7056): fixed works that need specialized engineering knowledge and skill, including highways, streets and roads, bridges, airports, sewers, pipelines, dams, levees, earthmoving, excavating, grading, trenching and paving.
• Class B, general building (B&P § 7057): structures for the shelter or support of people, animals or property that require at least two unrelated building trades or crafts. A B contractor may take a framing or carpentry contract on its own, but other prime contracts must involve at least two unrelated trades besides framing or carpentry unless the firm holds the right classification or subcontracts to a properly licensed firm.
• Class B-2, residential remodeling (B&P § 7057.5): improvements to an existing residential wood-frame structure that use at least three unrelated trades or crafts in a single contract.
• Class C, specialty (B&P § 7058): work that requires special skill in a specialized building trade or craft, such as electrical (C-10), plumbing (C-36), roofing (C-39) or earthwork and paving (C-12).

The $1,000 exemption

B&P § 7048 exempts work on one project whose aggregate contract price is less than $1,000, but only if the work needs no building permit. The exemption does not apply if the job is part of a larger operation, if contracts are split to evade the law, or if the person advertises as a contractor or employs anyone to do the work.

What the license file shows

This site's California directory is built from CSLB's License Master file (updated Oct. 28, 2026), limited to licenses with a current status and a California address. It holds 13,422 firms with Class A, 93,785 with Class B, 1,536 with Class B-2 and 105,142 with only C classifications. Each listing links to the CSLB record.

Public works registration

A CSLB license is not enough for public jobs. The Department of Industrial Relations says contractors and subcontractors must hold a current Public Works Contractor Registration before bidding on or working on a public works project, which includes construction over $25,000 and maintenance over $15,000. See our Caltrans bidding guide.

Summary for general information, reviewed 2026-10-30. Not legal advice; check the source before relying on a deadline or threshold.