Does Seattle issue its own contractor licenses?

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

How do I verify a Seattle contractor license?

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

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Seattle, Washington · contractor license lookup

How to verify a contractor license in Seattle, Washington

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

Seattle coverage: Operational · live status

What you can verify

Data source: Official Seattle licensing portal

Jurisdiction: Seattle (municipal), Washington

Trade types

Boiler OperatorGas PipingRefrigeration ContractorRefrigeration JourneymanRefrigeration Operator

Looking for the Washington state board instead? See the Washington 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:

GET /verify?state=WA&city=seattle&license=SAMPLE-12345&trade=boiler_operator

{
  "valid": true,
  "name": "SAMPLE CONTRACTING LLC",
  "license_number": "SAMPLE-12345",
  "trade": "boiler_operator",
  "expiration": "05/12/2027",
  "status": "Active",
  "state": "WA",
  "disciplinary_actions": [],
  "source_url": "https://services.seattle.gov/Portal/GeneralProperty/PropertyLookUp.aspx?isLicensee=Y&TabName=APO",
  "cached": false,
  "checked_at": "2026-08-03T18:00:00Z"
}

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

Verify Seattle licenses programmatically

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

The official Seattle licensing portal is at https://services.seattle.gov/Portal/GeneralProperty/PropertyLookUp.aspx?isLicensee=Y&TabName=APO — 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.

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Frequently asked questions

Does Seattle issue its own contractor licenses?: Yes. Seattle licenses certain trades at the city level rather than (or in addition to) the Washington state board. TradesAPI verifies Seattle municipal licenses through the same GET /verify endpoint, passing city=seattle alongside the state.
How do I verify a Seattle contractor license?: Call TradesAPI's GET /verify with state=WA, city=seattle, 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 Seattle trades can I verify?: TradesAPI covers these Seattle trade types today: Boiler Operator, Gas Piping, Refrigeration Contractor, Refrigeration Journeyman, Refrigeration Operator.