How to Verify a Contractor's License in California

Verifying a contractor's license in California takes 2 minutes and is one of the most important things you can do before authorizing work on your home. Here's exactly how to do it.

Step-by-Step: Verify a License at CSLB

1. Go to cslb.ca.gov
2. Click "Check a License" in the main navigation
3. Enter either the contractor's license number (they should give this to you directly) OR their business name OR their personal name
4. Review the results

What You're Looking For

License Status: Should say "Active." An expired, suspended, revoked, or inactive license does not authorize the contractor to accept work that requires that license.

License Classifications: Match the classification to the work. - C-10 for electrical work - C-20 for HVAC - C-36 for plumbing - C-39 for roofing - B for general building/remodeling

Business Name: Verify it matches who you're dealing with. Some contractors operate under multiple names (DBA - "doing business as").

Workers' Compensation Status: The CSLB page shows whether workers' comp is on file. "Exempt" is acceptable for sole-owner operators with no employees. If they have employees, workers' comp should be active.

Disciplinary Actions: Scroll down to see any complaints, citations, or disciplinary history. Multiple complaints are a clear warning sign.

What If They Don't Have a License Number?

Ask directly: "Can you give me your CSLB license number?"

If they: - Do not have one: They cannot take work that requires the relevant CSLB license - Give you a number that doesn't come up: Verify they spelled it correctly, then search by business name - Get defensive about the question: That's a red flag

Legitimate contractors expect this question and have their license number ready.

Searching by Business Name

If you don't have the license number, search by company name. The search is exact-match, so try variations: - "Acme Plumbing" vs. "Acme Plumbing Inc." vs. "Acme Plumbing Services"

If you get no results, try the owner's last name.

What a Suspended or Inactive License Means

Inactive: The contractor chose to put the license on inactive status. They cannot legally perform work. They may claim it's a paperwork issue - verify it's been fully reactivated before hiring.

Suspended: Disciplinary action or insurance lapse. Serious flag - do not hire.

Revoked: License permanently taken away. Do not hire under any circumstances.

Contractor License vs. Business License

These are different things: - Business license: A local registration to operate a business in a city or county. Required for most businesses. - CSLB contractor license: The state-level license required to do construction work.

Don't confuse a business license with a contractor's license. A contractor can have a business license without a CSLB license. Only the CSLB license matters for construction work.

Checking Insurance Separately

The CSLB page shows insurance status, but getting the actual certificate of insurance directly from the contractor is better. The certificate includes: - Policy number - Coverage amounts - Expiration date - Your address as an additional insured (for large jobs, ask for this)

Call the insurance company listed on the certificate to verify the policy is current. This takes 3 minutes and catches contractors using outdated or fake certificates.

How Often to Check

For a new contractor you've never used: Check before they start work.

For a contractor you've used before: Check annually or when they come for a significant project. Licenses can lapse.

For any contractor recommended by a neighbor or friend: Still check. The license situation could have changed, or the person doing your job might be different from who your neighbor used.

What to Do If They're Unlicensed

For lower-priced jobs: Do not assume unlicensed work is automatically legal. A permit requirement or use of additional workers can still trigger licensing rules. Verify the scope and current CSLB guidance.

For projects at $1,000 or more, or work requiring a permit or additional workers: Do not hire someone who lacks the required license. The risks (no recourse for bad work, liability for injuries, permit problems, insurance gaps) are real.

If you've already hired someone and discover they're unlicensed: Stop work, don't make further payments, and consult CSLB for options.

Bottom Line

Verifying a contractor's California license takes only a few minutes at cslb.ca.gov. Check that the status is "Active," the classification matches the work type, and the record does not show unresolved concerns. Verify before any project that requires a permit, uses additional workers, or reaches $1,000 in combined labor and materials.

Sources and editorial notes

Prices and permit requirements vary by location, property, equipment, and scope. Treat price ranges as planning estimates and confirm current requirements with the relevant authority and contractor.

• California Contractors State License Board - when a contractor license is required
• US Department of Energy - Energy Saver
• US Consumer Product Safety Commission - home safety

Related guides

• What to Check Before Hiring a Contractor (License, Insurance, Reviews)
• What HVAC Certifications Should Your Technician Have?
• How to Find a Reliable HVAC Technician Near You

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