How to Check a Contractor License in California

California licenses contractors through the Contractors State License Board (CSLB). Checking a contractor before you hire takes a few minutes on the CSLB website and protects you from a lot of trouble.

Step 1: Look up the license

Go to the CSLB website, cslb.ca.gov, and use "Check a License".
Search by license number, business name or personal name.
Confirm the license is active and the business name matches your contract.

Step 2: Check the classification

California licenses are issued by type. A general building contractor (B) can manage many projects, while specialty work uses "C" classifications, such as C-10 for electrical, C-36 for plumbing, C-39 for roofing and C-20 for heating and air. Make sure the license fits your job.

Step 3: Check bond and workers' compensation

Licensed contractors must carry a contractor's bond. The lookup shows it.
Contractors with employees must have workers' compensation insurance. The lookup shows it or an exemption.
Ask separately for proof of general liability insurance.

Step 4: Look for complaints and discipline

The license record shows public complaints and legal actions. A long license history with no actions is a good sign.

Know the down payment rule

For most home improvement contracts in California, the down payment cannot be more than $1,000 or 10 percent of the contract price, whichever is less. Swimming pools have different rules. A contractor asking for much more upfront is a red flag.

Other good habits

Get a written contract with the scope, price, payment schedule and start and finish dates.
Make sure the contractor pulls any required permits.
Do not pay ahead of the work done.
Get lien releases from the contractor and suppliers as you pay, so you are not stuck paying twice.

Small jobs

Very small jobs below a dollar limit set by state law may not need a license, but anything involving permits or licensed trades does. Check the CSLB website for the current limit.

How CSI helps

On CSI Elite Services, California pros' licenses are checked against the CSLB list, and verified pros show a badge on their profile.

Frequently asked questions

What if a contractor is unlicensed?

You lose many protections, and unlicensed contracting can be illegal for jobs that require a license. Choose a licensed pro.

Where do I complain about a contractor?

File a complaint with the CSLB. It handles complaints against licensed contractors and acts against unlicensed ones.

Find a verified pro near you, or post your job and compare bids from licensed contractors.