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How to verify a contractor license in Chicago, Illinois

Check any Chicago contractor license — status and expiration — through one normalized API, or look it up by hand on the city licensing portal. Chicago licenses trades at the city level, not just the Illinois state board.

What you can verify

Data source: Official Chicago licensing portal

Jurisdiction: Chicago (municipal), Illinois

Trade types

Looking for the Illinois state board instead? See the Illinois contractor license guide.

One call. State and city licenses, same schema.

The /verify response is identical in shape whether the license is issued by a state board or a city — add the city parameter and your integration code stays the same:

{
  "valid": true,
  "name": "SAMPLE CONTRACTING LLC",
  "license_number": "SAMPLE-12345",
  "trade": "electrical",
  "expiration": "05/12/2027",
  "status": "Active",
  "state": "IL",
  "disciplinary_actions": [],
  "source_url": "https://webapps1.chicago.gov/licensedcontractors/",
  "cached": false,
  "checked_at": "2026-06-22T05:14:00Z"
}

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

Verify Chicago licenses programmatically

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

The official Chicago licensing portal is at https://webapps1.chicago.gov/licensedcontractors/ — free to search by hand. TradesAPI wraps it in the same /verify call you use for every state, so city and state licenses come back in one normalized schema.

Frequently asked questions

Does Chicago issue its own contractor licenses?

Yes. Chicago licenses certain trades at the city level rather than (or in addition to) the Illinois state board. TradesAPI verifies Chicago municipal licenses through the same GET /verify endpoint, passing city=chicago alongside the state.

How do I verify a Chicago contractor license?

Call TradesAPI's GET /verify with state=IL, city=chicago, and the license number to get a normalized result — valid/invalid, status, and expiration — in one request, or search the city portal by hand.

What Chicago trades can I verify?

TradesAPI covers these Chicago trade types today: Electrical, Elevator, General Contractor, Masonry, Plumbing.