InstaBidsInstaBids
Skip to content
InstaBids
Menu
Use your AIConnector, agent API and ready promptsOpen in ChatGPTOpen in ClaudeOpen in GrokOpen in GeminiCopies the prompt, then opens
Add InstaBids to ClaudeMCP connector, sign in onceSteps for every assistantFor AI agents
How InstaBids works
Use your AIStart my request

How do you check a contractor license in Washington?

In Washington the statewide record is a contractor registration with the Department of Labor & Industries (L&I), on lni.wa.gov. L&I says you can look a registration up online or by calling its contractor information line, and that you can find the number in the contractor's advertisements and on your written bid.

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.
Source: Washington State Department of Labor & Industries, Problems with a Contractor, read 22 October 2026.
Source: Washington State Department of Labor & Industries, Hire Smart Step by Step, read 22 October 2026.

The license lookup is yours to run on the state's site.

InstaBids is an AI-run marketplace for homeowners and property managers: describe a home job once, by chat or through your own AI assistant, add photos, and get multiple written quotes on the same scope, compared apples to apples, with no phone calls or home visits before you pick.

By InstaBids editorial team with AI research agents. Sources last read: 22 October 2026

InstaBids assistantAI · builds your written scope with you

What home job do you need done in Washington? Describe it once to start your written scope.

Start from a common job
You choose who gets your number
Or send it from your own AIChatGPTClaudeGrokGeminiMore ways
  1. Describe it onceBy chat, or through your own AI assistant, and add photos.
  2. Post it and send itContractors bid in writing on that scope.
  3. Compare line by lineEvery quote is written against the same scope.
  4. You chooseContact details stay hidden until you pick and they confirm.
InstaBids

For your AI assistant

MCP connector · REST API · plain HTML

Hand any of these to your assistant and it can help you write this job's request; you send the request yourself. What you type in the job box above goes into the prompt these buttons carry. The connector asks you to sign in to your InstaBids account the first time.

  • MCP connector URLhttps://instabids.ai/api/agent/mcp
  • Agent API (OpenAPI)https://instabids.ai/openapi.json
  • Start-request linkhttps://instabids.ai/intake?from=licence-washington&utm_campaign=licence&page_type=licence&job=home+job&place=washington&utm_source=us&utm_medium=page
Open it in your assistantAdd InstaBids as a connector

Every page is plain HTML. Steps for every assistant: add to your assistant.

Key facts

Where do you look up a Washington contractor registration?

Start from L&I's Problems with a Contractor page, listed in the sources below: it points homeowners to L&I's online registration search and to its contractor information line by phone.

Source: Washington State Department of Labor & Industries, Problems with a Contractor, read 22 October 2026.

L&I's Hire Smart page says where the registration number is printed: "You can find your contractor’s registration number in their advertisements and on your written bid."

Source: Washington State Department of Labor & Industries, Hire Smart Step by Step, read 22 October 2026.

The same page explains why it should be there: "The law requires a contractor’s registration number to be included in all advertisements, including business cards and internet advertisements."

Source: Washington State Department of Labor & Industries, Hire Smart Step by Step, read 22 October 2026.

What does Washington require of a construction contractor?

L&I says Washington requires every construction contractor to register with L&I; section 18.27.020 of the Revised Code of Washington puts the same rule in one line. L&I also says that, for a contract over the amount quoted below, the contractor must have you sign a disclosure statement.

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.
Source: Washington State Legislature, Revised Code of Washington, section 18.27.020, read 22 October 2026.
Source: Washington State Department of Labor & Industries, Problems with a Contractor, read 22 October 2026.

L&I's registration page, read 22 October 2026, says: "Washington State requires all construction contractors to register with L&I."

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.

The statute reads: "Every contractor shall register with the department."

Source: Washington State Legislature, Revised Code of Washington, section 18.27.020, read 22 October 2026.

The registration page adds a second requirement: "State law also requires construction contractors to be bonded and insured to protect the public."

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.

L&I's page on problems with a contractor names the form: "If your contract exceeds $1,000, Washington laws [RCW 18.27.114(1) or (2)], require contractors to have you sign a disclosure statement."

Source: Washington State Department of Labor & Industries, Problems with a Contractor, read 22 October 2026.

It goes on: "The contractor must keep a copy on file for 3 years, you should also request a copy for your records."

Source: Washington State Department of Labor & Industries, Problems with a Contractor, read 22 October 2026.

How do Washington's general and specialty registrations differ?

Washington has two classifications: general contractors can do most types of construction work, while specialty contractors can work only in the specialty they are registered in, and L&I counts 63 specialties.

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.

The registration page says: "There are two classifications of construction contractors in the state:"

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.

On the first it says: "General contractors can perform most types of construction work."

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.

On the second: "Specialty contractors can only perform work in the specialty they are registered in."

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.

It also says: "L&I regulates 63 specialties that each require contractor registration."

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.

L&I's registration page adds that contractors working with plumbing, electrical, elevators, mobile home installation, boilers and asbestos have additional requirements for education, examination and licensing, on top of registration.

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.

So ask whether a registration is general or specialty, and which specialty it names.

Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.

What else does L&I tell Washington homeowners to look at?

On its hiring page, L&I lists what to look at, including the contractor's license history, and it is plain about what registration does not promise.

Source: Washington State Department of Labor & Industries, Hiring a Contractor, read 22 October 2026.

One item on that list reads: "Review a contractor’s license history for previous lawsuits or license violations."

Source: Washington State Department of Labor & Industries, Hiring a Contractor, read 22 October 2026.

On what registration does and does not do, the page says: "Hiring a registered contractor doesn’t guarantee that problems won’t happen, but it may give you protections that aren’t available otherwise."

Source: Washington State Department of Labor & Industries, Hiring a Contractor, read 22 October 2026.

L&I's page on problems with a contractor puts its advice this way: "Most contractor problems can be avoided by hiring a registered contractor, checking registration, and getting agreements in writing."

Source: Washington State Department of Labor & Industries, Problems with a Contractor, read 22 October 2026.

What should you ask a Washington contractor before you sign?

Get the registration number and whether the registration is general or specialty, then you can look it up on L&I's site as an optional public-record step. These are practical suggestions, not L&I rules.

  1. Ask for the registration number, and compare it with the one in the contractor's advertisements and on your written bid.

    Source: Washington State Department of Labor & Industries, Hire Smart Step by Step, read 22 October 2026.

  2. Ask whether the registration is general or specialty; if specialty, ask whether your job falls inside it.

    Source: Washington State Department of Labor & Industries, Register as a Contractor, read 22 October 2026.

  3. Look the registration up online on L&I's site, or call its contractor information line.

    Source: Washington State Department of Labor & Industries, Problems with a Contractor, read 22 October 2026.

  4. Review the contractor's license history for previous lawsuits or license violations, as L&I's hiring page suggests.

    Source: Washington State Department of Labor & Industries, Hiring a Contractor, read 22 October 2026.

  5. If your contract is over the amount quoted above, expect the contractor to have you sign a disclosure statement; read it, and ask for a copy for your records.

    Source: Washington State Department of Labor & Industries, Problems with a Contractor, read 22 October 2026.

Who sees your contact details when you post a job on InstaBids?

One point about InstaBids follows. Contact details stay hidden until the homeowner picks a contractor and they confirm the connection.

Source: InstaBids process and privacy, live-page excerpts, read 22 October 2026.

Post your job on InstaBids, and contractors can bid in writing on one written scope.

Homeowners anywhere in the US can post a job; once you send it, InstaBids finds contractors to bid on it.

Start my request

Sources for the facts on this page

Start my requestUse your AI