California Contractor License Classifications Explained
California uses a classification system to define what type of work each contractor is licensed to perform. There are over 40 classifications, and each one authorizes a specific scope of work. Hiring a contractor with the wrong classification for your project is the legal equivalent of hiring an unlicensed contractor.
This guide breaks down the system in plain language.
The Three Tiers: A, B, and C
All California contractor classifications fall into three tiers.
A: General Engineering
The A license covers infrastructure and civil engineering work: roads, bridges, dams, pipelines, utilities, and similar large-scale projects. Most homeowners will never hire an A-licensed contractor directly.
B: General Building
The B license is the most common general contractor classification. A B-licensed contractor can manage residential and commercial building projects that involve two or more trades. This includes new construction, remodels, additions, and renovations.
A B-licensed general contractor can self-perform some work and must hire properly licensed subcontractors for specialty trades like electrical, plumbing, and HVAC. The general contractor is responsible for managing the project and ensuring all work meets code.
C: Specialty Contractors
The C classifications are the specialty trades. Each one authorizes a specific type of work. Here are the most common classifications homeowners encounter:
- C-10: Electrical – Wiring, panels, lighting, and electrical systems.
- C-36: Plumbing – Pipes, fixtures, water heaters, and drainage.
- C-20: HVAC – Heating, ventilation, and air conditioning systems.
- C-39: Roofing – Roof installation, repair, and waterproofing.
- C-33: Painting – Interior and exterior painting, wallpapering, and coatings.
- C-27: Landscaping – Landscape design, irrigation, and outdoor structures.
- C-8: Concrete – Foundations, driveways, flatwork, and structural concrete.
- C-54: Tile – Ceramic, stone, and tile installation.
Browse the full list of over 40 classifications in the classification directory.
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Matching a Classification to Your Project
For single-trade jobs (replacing a water heater, rewiring a panel, patching a roof), hire a contractor with the specific C classification for that trade. For multi-trade projects (a kitchen remodel that involves plumbing, electrical, and tile), hire a B-licensed general contractor who will coordinate the specialty subcontractors.
If you are unsure which classification your project requires, describe the work to the contractor and ask which license classification covers it. Then verify that their license actually includes that classification. Some contractors hold multiple classifications.
Multiple Classifications
A single contractor can hold multiple classifications. For example, a contractor might hold both a B (General Building) and a C-36 (Plumbing) license, allowing them to manage full remodels and self-perform plumbing work. This is common and legal. Each classification on the license is listed on their CSLB record.
D Classifications: Limited Specialty
The C-61 classification includes a set of limited specialty subcategories identified by D codes. These cover niche trades like fencing (D-34), cabinet and millwork (D-06), and swimming pool maintenance (D-35). These licenses have a narrower scope than the main C classifications.