How do I verify a contractor license in California?

You can search the official California board portal by hand, or call TradesAPI's GET /verify endpoint with the state, license number, and trade to get back a normalized result — valid/invalid, status, expiration, and any disciplinary actions — in one request.

What contractor trades does California license?

TradesAPI covers these California trade types today: General Contractor.

Is California contractor license data free to check?

The California board's public portal is free to search manually. TradesAPI adds a single normalized API across all 50 states plus DC — every new API key includes 50 free verifications.

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California · contractor license lookup

How to verify a contractor license in California

Check any California contractor license — status, expiration, and disciplinary history — through one normalized API, or look it up by hand on the state board portal.

California coverage: Operational · live status

What you can verify

Data source: CSLB public data (weekly)

Coverage: General (A/B/C-classes), 40+ specialty classifications, bond + workers' comp

Trade types

General Contractor

California also supports name search — when you only have a contractor's name, the /search endpoint returns every matching license with full metadata.

City-level licensing in California

Some California trades are licensed by the city, not the state board. We also cover municipal licensing in Los Angeles under the same normalized schema and the same /verify call.

Trade-specific California lookups

Verifying one trade in particular? These guides go straight to the California lookup for that trade:

General Contractor →

One call. The whole picture.

The /verify response is identical in shape across every state, so your integration code never changes per jurisdiction:

GET /verify?state=CA&license=SAMPLE-12345&trade=general

{
  "valid": true,
  "name": "SAMPLE CONTRACTING LLC",
  "license_number": "SAMPLE-12345",
  "trade": "general",
  "expiration": "05/12/2027",
  "status": "Active",
  "state": "CA",
  "disciplinary_actions": [],
  "source_url": "https://www.cslb.ca.gov/onlineservices/checklicenseII/checklicense.aspx",
  "cached": false,
  "checked_at": "2026-08-14T07:00:00Z"
}

Example response showing the normalized schema. Wire it up against deterministic fixtures in the sandbox — no credit cost.

Verify California licenses programmatically

# Verify a California contractor license with one API call
curl -H "X-API-Key: YOUR_KEY" \
  "https://www.tradesapi.com/verify?state=CA&license=SAMPLE-12345&trade=general"

The official California board portal is at https://www.cslb.ca.gov/onlineservices/checklicenseII/checklicense.aspx — free to search by hand. TradesAPI wraps it (and every other state) in one API so you don't maintain 51 different scrapers.

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Frequently asked questions

How do I verify a contractor license in California?: You can search the official California board portal by hand, or call TradesAPI's GET /verify endpoint with the state, license number, and trade to get back a normalized result — valid/invalid, status, expiration, and any disciplinary actions — in one request.
What contractor trades does California license?: TradesAPI covers these California trade types today: General Contractor.
Is California contractor license data free to check?: The California board's public portal is free to search manually. TradesAPI adds a single normalized API across all 50 states plus DC — every new API key includes 50 free verifications.