How to Check a Contractor Before Hiring (US & UK, 2026)

Quick answer

To check a contractor, look up their license on your state licensing board (CSLB in California, for example), ask for a certificate of insurance sent by their insurer, confirm who will pull the permits, read reviews and complaints, and get at least three written quotes. Never pay the full price up front. In the UK, check Gas Safe Register for gas work, a registered competent person scheme for electrics, TrustMark, and Companies House.

Key numbers

$1,405median loss reported for home improvement scams in 2025, with 69.1% of reports involving a lossBBB Institute for Marketplace Trust, 2025 Scam Tracker Risk Report
No. 5home improvement scams' rank among the riskiest consumer scams in the US in 2025BBB Institute for Marketplace Trust, 2025 Scam Tracker Risk Report
10% or $1,000the most a California contractor can take as a down payment on home improvement work, whichever is lessContractors State License Board (CSLB)
18,000+businesses registered with TrustMark, the UK government-endorsed quality scheme for work in and around the homeTrustMark

You need a roof fixed, a kitchen redone or a boiler replaced, and you have a quote from someone you found online or who knocked on your door. Before you sign or hand over a deposit, you want to know they're licensed, insured and who they say they are.

Getting it wrong is expensive. Home improvement scams were the fifth riskiest scam type reported to the BBB in 2025: 69.1% of people who reported one lost money, with a median loss of $1,405. Most of that is avoidable with about 30 minutes of checks.

How do I check if a contractor is legit?

Check five things before you sign: their license, their insurance, their identity and business record, their reviews and complaints, and the contract itself. Do them in this order:

License. Look up the license number on your state or county licensing board. Confirm the name, status (active, not expired or suspended), and that the license covers the type of work.
Insurance. Ask for a certificate of liability insurance and, if they have employees, workers' compensation. Have the insurer send it to you directly.
Identity and business. Make sure the person in front of you matches the business on the license. Check the address, phone and company registration.
Reviews and complaints. Search the business name with “complaint”, “scam” and “review”, check the BBB and your state attorney general, and call two or three recent customers.
Quotes and contract. Get at least three written quotes, then a written contract with no blanks before any work or payment.

How do I look up a contractor's license?

Search for your state's contractor licensing board and use its free license lookup, which shows whether a license is active and what work it covers. The FTC's advice is simply to check with your state or county government to confirm a contractor's license.

Find your state board

The National Association of State Contractors Licensing Agencies keeps a directory of state licensing agencies with links to each verification tool. If your state isn't listed, search “[your state] contractor license lookup”. Licensing rules vary a lot: some states license general contractors at state level, others leave it to cities or counties, and many license trades like electricians and plumbers separately. If the state doesn't license the work, check your city or county.

Example: California (CSLB)

In California, use the Contractors State License Board to check the license number. Since January 2025, unlicensed people can only do jobs under $1,000 that need no permit and where they don't hire workers, under AB 2622. California also caps the down payment at 10% of the contract price or $1,000, whichever is less, and requires a written contract for home improvement jobs over $500.

What to look for on the license record

The business name and owner match the person quoting you.
Status is active, not expired, suspended or revoked.
The license class covers your job (roofing, electrical, general building).
A bond and workers' comp are on file, where your state records them.
No recent disciplinary actions, or ones you've asked about and understood.

How do I verify a contractor's insurance and bond?

Ask for a certificate of insurance (often called a COI), then call the insurer or agent named on it to confirm the policy is active and covers the dates of your job. A photo of a certificate proves little, because certificates are easy to edit and policies can be cancelled after they're issued.

General liability covers damage to your property.
Workers' compensation covers injuries to their crew. Without it, an injured worker may look to you or your homeowner's policy.
A license bond (required in some states) gives you a limited claim if the contractor breaks licensing law. It's not insurance for poor work, and the amount is often small.

Ask your own home insurer what they expect from contractors before large jobs. Some policies exclude damage caused by unlicensed work.

Who should pull the permit, me or the contractor?

The licensed contractor should pull the permit for work that needs one. The FTC lists a contractor asking you to get the permits as a red flag: it can mean they're unlicensed or want to avoid inspection, and it puts the legal responsibility on you. Your city or county building department can tell you whether the job needs a permit, and many let you look up permits by address online, which also shows a contractor's past jobs.

How do I check reviews and complaints?

Use several sources, because star ratings can be faked. Search the business name and the owner's name with “scam”, “complaint” and “lawsuit”. Look at the BBB profile for complaint patterns and how they were answered, and check your state attorney general or consumer protection office. Then ask for two or three customers from the last year with similar jobs, and call them.

It also helps to check the person, not only the company. Bad operators often close one business and open another under a new name. A Search A-Z search on the owner's name and city shows their current company, work history, public profiles, news and web mentions, and any public scam or fraud warnings, and checks whether the phone number and email they gave you are real or flagged for fraud risk. The person is never told you searched. For the business itself, our guide on how to check if a company is legit covers registration and website checks.

What questions should I ask a contractor before hiring?

Ask questions that make them give you checkable facts, then check them:

What's your license number, and what name is it under?
Can your insurer send me a certificate of liability and workers' comp insurance?
Will you pull the permits and schedule the inspections?
Who will actually do the work? Do you use subcontractors, and are they licensed?
Can I speak to three customers from the last year with similar jobs?
What's the payment schedule, and what do you need up front?
What warranty do you give on labor, and what manufacturer warranties apply?
How do you handle changes and unexpected costs? (The answer should be: written change orders signed by both of us.)

“Before we go further, can you text me your license number and have your insurance agent email me a certificate? I check those with every quote.”

A real contractor will say yes without fuss. Someone who stalls, gets angry or drops the price instead is telling you something.

What are the red flags of a bad contractor?

They knock on your door saying they're “in the area” or have materials left over from another job.
They pressure you to decide now, or offer a discount only if you sign today.
They want full payment up front, or cash, wire, gift cards, a payment app or crypto only.
They ask you to get the permits.
They say no license is needed for the work.
They want you to sign over your insurance check.
They steer you to a lender they know, or offer to help with FEMA aid for a fee.
Only a mobile number, no business address, and a vehicle with no business name.
A quote far below the others, or a contract with blank spaces “to fill in later”.

Storm chasers

After hail, hurricanes and floods, out-of-area crews go door to door. The FTC's disaster scam advice is clear: verify coverage with your insurer yourself, never sign over the insurance check, and know that FEMA doesn't charge application fees. Ask your bank about a certificate of completion, which pays the contractor in stages as you approve each one.

Deposit scams

The most common loss is a deposit paid to someone who never comes back. Keep the deposit small (check your state's cap), pay by credit card or check, never cash, and tie later payments to finished stages of work.

What should a contractor's contract include?

A good contract puts every promise in writing. Use this checklist, built from CSLB and FTC guidance:

Contractor's name, business address, phone and license number.
A detailed description of the work, materials, brands and models.
Total price and a payment schedule where payments never run ahead of finished work.
Who obtains permits, and that work passes inspection before final payment.
Start and completion dates.
Written change orders, signed before any change.
Cleanup and debris removal.
Labor warranty and manufacturer warranties.
Your cancellation rights, and no blank spaces.

If you sign at home and the job is $25 or more, the FTC's Cooling-Off Rule generally gives you until midnight of the third business day to cancel. It doesn't apply if you asked them to come for a repair, or to genuine emergencies. Never make the final payment until the work is done and inspected.

How do I check a builder or tradesperson in the UK?

In the UK, check the trade-specific register first, then the company. Some of these are legal requirements, not just nice to have:

Gas work: by law, the engineer must be on the Gas Safe Register. Ask to see their ID card: the front shows their photo, license number and business, the back lists the gas work they're qualified for. You can check on the register's website or call 0800 408 5500.
Electrical work: use an electrician registered with a competent person scheme such as NICEIC, so they can certify the work meets building regulations.
General trades: TrustMark is the only government-endorsed quality scheme for work in and around the home, with over 18,000 registered businesses. Check any trade association claim on that body's own member list.
The company: search Companies House for free to see if it's active, who the directors are, filed accounts and any insolvency. A Search A-Z business search also shows UK Companies House roles for the person.

Citizens Advice suggests three written quotes, staged payments and a deposit of no more than 25%. If you agree the work at home or online, you usually get a 14-day cooling-off period. Paying part by credit card for a job between £100 and £30,000 can add Section 75 protection.

EU: rules differ by country, so check the national register for the trade. In Ireland, electricians must be Safe Electric registered and gas installers must be RGI registered. In France, builders must carry decennial insurance, so ask for the “attestation décennale” before work starts. Everywhere, check the company in the national business register and keep payments staged.

Bottom line

Check the license, confirm insurance with the insurer, make the contractor pull the permits, and get everything in a written contract with a small deposit and staged payments. If someone pressures you, wants cash up front or can't give you a license number, find someone else. For a wider look at checking people you hire or work with, see our guide on people search vs background check.

Frequently asked questions

How do I check if a contractor is licensed?

Use your state contractor licensing board's free license lookup. Search the license number or business name and confirm it's active and covers your type of work. NASCLA lists state agencies with links to their verification tools. If your state doesn't license the trade, check your city or county.

How can I check a contractor's insurance?

Ask for a certificate of insurance, then call the insurer or agent named on it to confirm the policy is active for your job dates. Ask for general liability and, if they have employees, workers' compensation.

How much deposit should I pay a contractor?

As little as possible, and never the full price. Some states cap it: California allows 10% of the contract price or $1,000, whichever is less. In the UK, Citizens Advice suggests no more than 25%. Pay by card or check, not cash.

What is a storm chaser contractor?

A crew that follows severe weather, going door to door offering quick repairs. Warning signs include pressure to sign now, asking you to sign over your insurance check, wanting full payment up front, and saying no license is needed.

Can I check a contractor with Search A-Z?

Search A-Z can help confirm the person is who they say they are: current company, work history, public profiles, news and web mentions, public scam warnings, and whether their phone and email are real. It doesn't check licenses, insurance or court records, so use your state board for those. It's not for employment screening.

How do I check a builder in the UK?

Check the trade register (Gas Safe Register for gas, a competent person scheme like NICEIC for electrics), TrustMark, and the company on Companies House. Get three written quotes, stage payments, and pay part by credit card for Section 75 protection.

Sources

Figures are the latest published by each source when this guide was updated. Reported fraud losses are a floor: most fraud is never reported.

How to check a contractor before you hire them: licenses, insurance, reviews and red flags