California Contractor License Classifications Overview
California organizes licenses into engineering, building, and specialty classifications. Here is how they fit together.
Last reviewed July 22, 2026
The three families
Class A covers general engineering, Class B covers general building, and the many Class C classifications cover specialty trades.
Choosing the right classification
Pick the classification that matches the work you perform and the experience you can document. Regardless of choice, you still pass the Law & Business exam.
- A — General Engineering
- B — General Building
- C — Specialty trades (electrical, plumbing, landscaping, and more)
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How many classifications are there?
There are more than 40 classifications across engineering, building, and specialty trades.
Do all classifications take the Law & Business exam?
Yes. It is the universal requirement for California contractors.