How to Vet Subcontractors Before You Give Them a Job

To vet a subcontractor, verify their licence in the official database for your country or state, call their insurer directly to confirm active cover, speak to two past clients, and give them a small paid trial job before trusting them with anything bigger. That sequence has filtered my sub database to 1,400+ vetted trades - and it is the only reason the model works.

Here is how I run each step.

What vetting subcontractors actually means#

Finding a sub and vetting a sub are two different things. Finding is covered in how to build your subcontractor bench. Vetting is what you do once someone is in front of you. It is a structured sequence of checks - on paper, on the phone, and on a real job - that answers one question: can I trust this person with a client's money and my reputation?

The model only works if you are the main contractor in the background, not the person doing the work. That is construction arbitrage in a sentence: win the job, sub it out, make the spread. But the whole thing depends on the sub you pick delivering what you promised.

Step 1 - collect the basics before you meet#

Before I agree to meet any new sub, I ask for:

• Full legal name or registered company name
• Business registration number (or UTR in the UK)
• Licence number for the trade (where required)
• Name and contact for their insurer

Anyone who cannot send this in a message within a day is already a yellow flag. Good trades have this on their phone. They send it without being asked twice.

Step 2 - verify their licence in the official database#

This is non-negotiable and takes about three minutes. Every regulator has a free public lookup.

United States: every state runs its own licensing board. Key examples - the CSLB in California (cslb.ca.gov), the Department of Labor and Industries in Washington (lni.wa.gov), the DBPR in Florida, and the TDLR in Texas. Search for your state plus the trade and you will find the lookup tool. Type in the licence number and confirm it is active, the expiry date, and any complaints or violations on record.

United Kingdom: before you pay a sub a single pound, you must verify their Construction Industry Scheme (CIS) registration with HMRC. This is a legal requirement on you as the contractor. Do it through the CIS online service at gov.uk. If they are not registered, you deduct 30% from payments - or you can refuse to work with unregistered subs altogether, which is what I do.

Australia: licensing is state-by-state. The Fair Work Ombudsman governs employment conditions, but trade licences are issued at the state level. WorkClear (workclear.com.au) covers most states in one search. Check the licence is active and matches the trade you are hiring for.

Canada: provincial licensing bodies govern most trades. Ontario uses the College of Trades; British Columbia uses the Industry Training Authority; Quebec has the RBQ for construction contractors. Look up your province's body and run the check.

No licence, no work. For regulated trades - gas, electrical, structural - there is no workaround.

Step 3 - call the insurer directly#

A certificate of insurance is not proof of insurance. Certificates can be out of date, cancelled after they were issued, or in rare cases simply fabricated. I call the insurer directly.

The number to call is the one printed on the policy document itself - not a number the sub gives me. I confirm:

• Is this policy currently active?
• What is the expiry date?
• What is the general liability coverage amount?
• Does the policy cover [the specific work type I am hiring for]?

For standard trades - carpentry, plastering, painting, groundworks - I require at minimum $1 million per occurrence general liability. For higher-risk work - electrical, plumbing, roofing, demolition - I require $2 million GL minimum. Those are the industry-standard thresholds; your own contracts may require more depending on the job size.

Workers' compensation is required by law in 49 US states for any sub who employs people. Texas is the only state where it is technically voluntary for private employers, but most commercial contracts require it regardless. In the UK, employer's liability insurance is a legal requirement the moment a sub has any staff. Ask for the employer's liability certificate separately.

I ask to be named as an additional insured on their GL policy. Not all subs will agree on a first job, but the better ones do.

Step 4 - check their online footprint#

Spend five minutes on Google. Search their business name and their personal name. Look at:

• Google Business reviews and how they respond to negative ones
• Trade directories (Checkatrade in the UK, Angi and HomeAdvisor in the US, HiPages in Australia)
• Local community and Facebook groups where tradespeople get discussed

A pattern of complaints about no-shows, unfinished work, or disputes over payment tells you what you need to know. No footprint at all - no reviews, no web presence, nothing - is also worth noting on a trade who claims to have years of experience. Real busy trades leave traces.

Step 5 - call two references, live#

I call two past clients. Not one. Two. One recent job and one from at least a year ago. The time gap matters: it tells you whether someone was good once and has since declined, or whether they are consistently reliable.

I ask both the same three questions:

1. Did they finish the job on time?
2. Was the quality of the work what you expected when you agreed the scope?
3. Would you hire them again?

I call. I do not accept written testimonials or text snippets - those are easy to fake or cherry-pick. A real reference call takes four minutes and tells you more than any document.

Step 6 - see finished work in person or on video#

I ask every new sub for a finished job I can visit, or at minimum a video walkthrough of something they have completed. Photos are easy to pull from Google Images or steal from another trade. A video of a real finished space is harder to fake. A site visit is better still.

Trades who have good work are proud of it. They will offer to show you. Hesitation is a signal.

Step 7 - get pricing in writing before you quote anything#

This is operational, not a trust check - but it belongs in the vetting sequence because skipping it destroys your margin later.

Before you ever quote a client, confirm the sub's rate in writing. A WhatsApp message is fine. An email is better. The number you need: their rate for the job type, inclusive of what they bring. No vagueness. If you quote a client and then find out the sub's rate has moved, you absorb the difference.

Step 8 - the trial job#

This is the step most people skip and the step that matters most.

All the checks above tell you whether a sub is legitimate and claims to be good. The trial job tells you whether they actually are. I start every new sub - regardless of how strong their references are - on a small, low-risk job. Something where I can recover if it goes wrong without losing a client relationship.

On the trial I watch:

• Punctuality. Did they show up when they said?
• Communication. Did they message when they arrived, when they hit a snag, when they were done?
• Quality. Is the finished work what I agreed to deliver to the client?
• Site discipline. Did they leave the space clean? Did they cause problems for any other trades?

The trades who pass that - all of it, not just most of it - go on my A-bench. They get the bigger jobs, the priority calls, and the steady work that makes me worth their time. The ones who don't pass it don't get a second job.

Cowboys reveal themselves on the small jobs. Test cheap, then trust expensive.

Red flags that end the conversation early#

Some things I do not wait for a trial to rule out:

• No insurance or unwilling to provide a certificate
• Licence number that does not verify in the database
• Refuses to give references
• Asks for a large cash deposit upfront before any work starts
• Can't give a clear answer on their rate before you agree to work together
• Goes quiet for days between messages during the vetting process

Any one of those and I move on. There are enough good trades. The time I spend chasing a bad one is time I could spend building the bench with someone who passes.

How this connects to managing the work#

Vetting is the front end. Once they are on a job, the system that keeps the work on track is a different discipline - regular check-ins, milestone photos, and payment tied to progress. I go into that in detail in managing subcontractors remotely.

And on the insurance side, if you want to understand what cover you - the main contractor - need to carry, that is in what insurance do you need for construction arbitrage.

Build the bench carefully and you are not scrambling every time a new job comes in. The whole system for running this as a business - clients, subs, systems - is what THE FAMILY SECRET - How Construction Arbitrage Really Works covers in full. Coming soon.

Last checked: 13 July 2026.