California Contractor License Classifications

A California contractor license covers the classes printed on it, not all construction work. Electrical work falls under C-10 and roofing under C-39. Below $1,000, with no building permit and no helpers, a job needs no license at all.

Three Branches of Contracting

Business and Professions Code section 7055 splits contracting into three branches: general engineering, general building, and specialty contracting. General building has two parts: general building and residential remodeling.² The Contractors State License Board (CSLB) names them A, B, B-2 and C.¹

• A General Engineering: fixed works that need specialized engineering knowledge. Examples are irrigation, dams, highways, sewers, pipelines and power plants.³
• B General Building: structures for shelter or enclosure. The work must use at least two unrelated building trades or crafts.⁴
• B-2 Residential Remodeling: improvements to an existing residential wood frame structure. A single contract must use at least three unrelated trades.⁵
• C Specialty: construction work that needs special skill in a specialized building trade or craft.⁶

The CSLB classification list names 43 specialty classes, from C-2 to C-61.¹ One license can hold several classes. The licensee must qualify for each one, and CSLB charges no license fee for an added class.⁷

C-10 Electrical

A C-10 contractor places, installs, erects or connects electrical wires, fixtures, appliances, apparatus, raceways and conduits. The class covers any part of these that generates, transmits, transforms or uses electrical energy.⁸ The CSLB text also names solar photovoltaic cells.⁸

Solar panels can fall under two classes: C-10 and C-46 Solar both name photovoltaic systems.^8,13 The full hiring checklist is in Hiring an Electrician.

C-39 Roofing

A C-39 contractor installs products and repairs surfaces that seal, waterproof and weatherproof structures. The goal is to stop water from passing the roof into the space below.⁹ The CSLB text lists the materials: asphaltum, pitch, tar, felt, glass fabric, urethane foam, metal roofing, shakes, shingles, roof tile, slate, and membranes.⁹

Permits and other rules for a new roof are in Reroofing Rules.

Classes a Homeowner Meets

Why the Class Must Match the Job

Section 7059 lets CSLB limit a licensee to the fields in which the licensee is classified and qualified.⁷ A specialty contractor may still take a contract that uses other trades. The other trades must be incidental and supplemental to the licensed one.⁷

CSLB gives homeowners a simple rule. For a single-trade job, such as roofing or plumbing alone, hire a contractor licensed in that trade.¹⁴ When a job needs more than two types of work on a building, a B contractor may contract for and oversee the whole project.¹⁴

The Minor Work Exemption

Section 7048 exempts work on one project when the total price for labor, materials and all other items is less than $1,000. The work must also not require a building permit.¹⁵ The exemption is lost in three cases:¹⁵

• the work is part of a larger operation, or a job is split into contracts under $1,000;
• the person advertises or signals to the public that they are a contractor;
• the person employs anyone to do or help with the work.

The limit rose from $500 to $1,000 on January 1, 2025, under Assembly Bill 2622 (Stats. 2024, Ch. 240).¹⁶ The section was last amended by Assembly Bill 1170 (Stats. 2025, Ch. 67), effective January 1, 2026. The current text keeps the $1,000 limit.¹⁵ An unlicensed person may advertise work up to $1,000 only if the ad says they are not licensed.¹⁶

When the License Is Missing

A person who does licensed work without a license cannot sue in a California court to collect payment for it.¹⁷ A person who used an unlicensed contractor may sue to recover all compensation paid.¹⁷ Details are in Unlicensed Contracting. How to find the classes on a license is in How to Read a CSLB License Record.