Step 1: Ask for the license number in writing — not a photo of a card, the actual number.
A physical card tells you nothing. License cards get borrowed, expire, and get faked. You need the number so you can verify it yourself against the state's records. If a contractor hesitates to give you the number, or gives you a name instead of a number, stop the conversation there.
Do not schedule work off a verbal "yeah, I'm licensed." Get the number typed into a text or email so you have it in writing before anything else happens.
Step 2: Look up the license on your state board — and read the classification
Every state has a license lookup site. Search "[your state] contractor license lookup" and go to the .gov result, not a third-party directory.
When the record loads, don't just confirm it says ACTIVE. Read the classification field. This is the part almost nobody checks. A general building contractor (often "B" or "GC") is licensed to coordinate a project — but that classification does not automatically authorize them to perform electrical, plumbing, HVAC, or roofing work themselves.
Many states require a separate specialty classification for each trade: C-10 for electrical, C-36 for plumbing, C-20 for HVAC, C-39 for roofing (California letters shown as an example — your state's codes differ). Match the classification on the record to the actual work you're hiring for.
A GC can legally run the job. Whether they can legally rewire your panel is a completely different license question — and homeowners almost never ask it.— State licensing board investigator
Step 3: If the job touches a specialty trade, ask who holds that license
If your general contractor is subbing out the electrical or plumbing, ask for the sub's license number too — and verify it the same way.
Script you can copy: "Who's doing the electrical, and what's their license number and classification? I want to verify it before we start."
A legitimate contractor answers this without friction. They deal with it constantly. Evasion here is the whole ballgame.
Step 4: Confirm the license is bonded and insured for that class
On the same lookup page, check for an active bond and workers' comp status. Then request a Certificate of Insurance (COI) sent directly from their insurer or agent — not a PDF they email you themselves.
The COI should name the trade being performed. General liability coverage written for "carpentry" may not cover a roofing claim. Ask the agent directly: "Does this policy cover [your specific work]?"
Step 5: Cross-check the name on the license against the name on the contract
The license number you verified must belong to the business or person you're actually signing with. "Borrowed license" jobs — where an unlicensed operator uses a licensed friend's number — fall apart exactly here. The name on the state record and the name on your contract have to match.
The one red flag in almost every bad hire
They want a large deposit up front, in cash or by a method you can't reverse — before any verifiable work begins.
Every version of the bad-hire story runs through this. The unlicensed operator, the wrong-classification job, the borrowed-license scam — all of them need your money before you've confirmed anything. A contractor confident in their license and their work does not need to be paid before they've earned it.
The cleanest way to remove that risk entirely is to structure payment so funds are only released as verified milestones are completed — which also gives you a paper trail if the classification, insurance, or workmanship ever comes into question.