How to Get Subcontract Work From Main Contractors
The short answer
Main contractors give packages to firms already on their approved supplier list. Get on it by calling the estimator or QS (not sending a brochure), sending a short compliance pack the same day, pricing small packages fast and accurately, then delivering one awkward job perfectly.
- The approved list is the tender. Most main contractors only send packages to subcontractors already on their supply chain list.
- Target the right size. Contractors turning over roughly £5–15M subcontract packages constantly and still answer the phone.
- Call the estimator or QS. They decide who prices. Emails to info@ addresses rarely reach them.
- Have the pack ready before you call. Insurances, CIS, health and safety, RAMS, cards and three case studies, in one PDF.
Main contractors don't find subcontractors on Google. They ring the firms already on their approved list. If you're not on it, you never see the drawings.
The good news: getting on that list is mostly about who you call, what you send and how you behave on the first small package. This is the route we teach, and the one Sviat used himself when he moved from trades into running Craftex. Want a plan built around your trade? Book a free strategy call.
How main contractors actually pick subcontractors
When a main contractor wins a job, the estimator or commercial team splits it into packages: drylining, decorating, M&E, joinery, flooring. Each package goes out to two to five firms on their supply chain list. The best price from a firm they trust usually wins.
Three people matter:
- The estimator Builds the tender and asks subcontractors for prices before the job is even won.
- The QS or commercial manager Places packages once the job is live and manages your payments.
- The project or site manager Tells everyone whether you turned up and finished.
The approved list is the real tender. Once you're on it, you're invited to price. Until then, nothing you send gets opened.
Pick the right main contractors
Don't start with the national names. Their onboarding is long, and they often want years of track record and high insurance levels before you price anything.
Start with firms turning over roughly £5–15M a year. They subcontract packages constantly, their estimators still answer the phone, and a reliable small firm quickly becomes important to them. A few relationships like this can be worth £0.5–1.5M of turnover a year.
- Do they build the kind of job you do (fit-outs, resi refurbs, schools, housing)?
- Do they work in your area, within a sensible drive?
- Is their typical package size right for your team? A £400K package can sink a six-person firm.
- Are they winning work right now? Live sites, planning approvals and contract award lists tell you.
To find them, walk past live sites and note the names on the hoardings. Check who won recent contracts on award lists (services such as Builders Conference publish tender lists and awards). And ask your suppliers who they deliver to.
Not sure which contractors fit your size?
Book a free call and we'll build the target list with you.
Build the subcontractor pack before you call
The fastest way to lose a contractor's interest is "I'll send that over next week". Have one PDF ready, updated every quarter.
| Document | Why they ask for it |
|---|---|
| Public liability insurance | Every contractor asks; check the level each one requires |
| Employer's liability insurance | A legal requirement if you employ people |
| CIS registration (UTR) | The contractor must verify you with HMRC before paying you |
| Health and safety policy | Must be written down if you have five or more employees |
| RAMS templates for your trade | Asked for before you start on most sites |
| Training and card records | Most main contractors want card-carrying operatives on site |
| Last accounts or a bank reference | Shows you can carry a package until payment |
| Three case studies with a reference | Proof you've done their kind of job at this size |
Many larger contractors also ask for a pre-qualification certificate such as CHAS, Constructionline or Achilles. One assessment under the industry's Common Assessment Standard can satisfy several buyers. Don't buy it on spec, though.
I made this mistake myself. At Craftex I paid a lot for accreditations, and on their own they never paid off. Get an accreditation only when a specific tender for a specific project asks for that specific accreditation. Most schemes take 2–3 months, so you will have time once the request is real. Don't buy them hoping work will start pouring in. It won't.
Make the call: estimator or QS, not reception
Call the office and ask for the estimator or the QS by name if you have it. Spend one or two days a week only on this. It's a numbers game.
Keep it short. Something like:
"Hi, it's [name] from [company]. We're a [trade] contractor, [X] people, working on [type of job] around [area]. I know you're busy, so one question: do you need help pricing [trade] packages at the moment? We turn prices round in 48 hours."
Then listen. Ask what they're pricing now, how their supply chain registration works, and who places packages once a job is won. Write it all in your CRM with a call-back date.
Sending a brochure to info@ and waiting. Nobody forwards it. One phone call to the right person beats 50 emails.
The same works face to face. Oleg, 19, visited 15 sites in central London in two hours and walked away with a real project opportunity. A site manager with a labour problem today is the warmest lead you'll ever get.
Price fast, accurately and with your terms
Your first prices are an audition. The estimator is checking three things: speed, accuracy and whether you read the drawings.
- Reply inside the deadline, ideally early. Late prices go in the bin.
- Price the package they sent, not the one you'd like. List every assumption and exclusion.
- Don't buy the job. A loss-making first package teaches them your real price is lower than it is.
- Ask for feedback when you don't win. "Were we high, and by roughly how much?" Most estimators will tell you.
If your prices keep coming back too high, the problem is usually your overheads or your rates, not the market. Our pricing guide shows how to build rates from your own jobs. Still losing every package on price? Book a free strategy call and we'll go through your rates with you.
Deliver the first package perfectly
The first package is often a small, awkward one, the job nobody else wanted. Treat it as the most important job of the year.
- Turn up on the day you said, with the right number of people and the right cards.
- Send RAMS before you start, not on the morning.
- Keep the area clean and sign off as you go.
- Raise problems early, in writing, with a solution.
- Invoice exactly in line with the subcontract and the payment schedule.
Do that and you become the firm they call when another subcontractor lets them down. That is how one £8K package turns into a £150K one.
Protect your cash before you sign
Main contractor work can be steady, but it can also leave a small firm carrying cash for months. Read the subcontract before you sign it.
| Term | What to check |
|---|---|
| Payment terms | How many days from application to payment, and the final date for payment |
| Retention | The percentage held and exactly when each half is released |
| Pay-less notices | How and when they can reduce what they pay you |
| Set-off and contra charges | What they can deduct and on what evidence |
| Programme and damages | Whether delays can be passed down to you |
If you're already chasing money, read what to do when a main contractor doesn't pay and how to respond to a pay-less notice.
20+ Ways to Get Construction Projects in the UK
Scripts for calling estimators and QSs, plus the other 21 ways builders find work, in one 24-page PDF.
Get the free guideWant a plan to get onto three new supply chains in the next 90 days?
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When subcontracting is a stepping stone, not the destination
Subcontract work is a great base: steady volume, no marketing cost, bigger projects on your CV. Just registered your company and have no work at all yet? Follow our 30-day plan to win your first clients. But you sit at the bottom of the payment chain and you rarely set your own margin.
Many of the owners we mentor use main contractor work to fund the team, then win their own clients alongside it. If that's your plan, read how to go from subcontractor to main contractor. To see where your business stands on sales, pricing and cash, take the free 4-minute Construction Business Scorecard.
BizMentor is one-to-one mentoring by Sviat Jay, who runs a working London construction company, Craftex. He works through your target list, your pack and your pricing with you, and most owners see results within about four months. Individual results, not typical or guaranteed.
This is general information from a contractor's experience, not legal or financial advice. On the tools and under £500K a year? Watch our free training first.
Before you call your first main contractor
- A target list of 20 contractors turning over £5–15M in your area
- One compliance PDF with insurances, CIS, H&S, RAMS and case studies
- A 30-second call script and a CRM with call-back dates
- Rates you trust, so your first prices are fast and right
- A rule to read payment, retention and pay-less terms before signing
