Main Contractor Contra Charges? A Subcontractor's Plan
The short answer
A contra charge is a deduction for something the main contractor says you caused. To take it from a payment, they need a valid payment or pay less notice on time, and they must be able to show your breach, the cost it caused and that they paid it.
- No valid notice, no deduction. To pay less than the notified sum, the main contractor needs a payment notice or pay less notice on time, with the sum and how it was worked out.
- They have to prove it. The paying party must show what you did wrong, that the cost came from it, and that it really spent the money.
- Reply in writing within days. Ask for the breakdown, the evidence and the clause they rely on. Dispute each line, not the whole bill.
- Stop the next one at tender stage. Agree in the subcontract that no contra charge is made without written notice and a chance to put it right.
The payment comes in £2,400 short. In the notice there's one line: "contra charges as attached". The attachment is a list you've never seen: cleaning, a damaged door, two days of labourers, and "programme delay".
We sit on the other side of this. Craftex runs subcontract packages as a main contractor. Our commercial team issues the notices and, when a trade causes a cost, charges it back.
Here is what a fair contra charge looks like, and how to push back on one that isn't. To go through yours with our team, book a free strategy call.
This is general information from a contractor's experience, not legal advice. For your situation, speak to a construction solicitor or a quantity surveyor.
What a contra charge is (and what it isn't)
A contra charge (or back charge) is money the main contractor takes off what it owes you. It's for a cost it says you caused. It's a claim against you. That means the main contractor has to prove it, not you.
- Cleaning and rubbish
- Damage to other trades' work
- Labour to cover your gaps
- Delay to the programme
- Defects put right by others
- Materials or plant you used
It is different from a lower valuation. If they say you've done 60% of the work, not 70%, that's a valuation argument: answer it with measures. A contra charge says "you did X wrong, and it cost us £Y". Answer it with evidence.
The first 48 hours: 5 checks
Put your subcontract, your application and their notice side by side. Check these five things before you pick up the phone.
| Check | What to look for | If it fails |
|---|---|---|
| 1. In a notice, on time? | The deduction is in a payment notice or pay less notice, before the deadline | It can't reduce this payment: the notified sum is due |
| 2. Sum and basis? | Each charge has an amount and how it was worked out | Ask for the workings in writing |
| 3. Clause? | The subcontract clause that lets them charge you | Ask which clause they rely on |
| 4. Notice to you? | You were told about the problem and given a chance to fix it | Strong point in your reply |
| 5. Real cost? | Timesheets, invoices, photos showing the cost was paid | Ask for them line by line |
Under the statutory Scheme, a pay less notice must arrive at least 7 days before the final date for payment. Your subcontract can set different dates: use those. These rules apply to contracts between businesses, not to work for a homeowner in their own home.
Problems like this usually trace back to cash and contracts. Take the free 4-minute Construction Business Scorecard: 18 questions on your pipeline, sales, pricing, cash flow and systems, with your weakest area shown first.
Still losing money to contra charges?
Book a free call with our team. We'll go through the charge, your subcontract and what to send back this week.
What the main contractor has to prove
The party making the deduction carries the burden of proof. To make a contra charge stick, the main contractor has to show three things:
- Breach You failed to do something the subcontract required, and how.
- Cause The cost came directly from that failure, not from other trades or its own planning.
- Cost It really spent the money. A round "£500 cleaning" with no timesheet is weak.
When we charge a trade back on a Craftex job, we send the photos, the dates and the cost with the notice. If we can't evidence it, we don't charge it. That's what "firm with clients, fair with subcontractors" means in practice. Expect the same from your main contractor, and ask for it.
Defective work is slightly different. A main contractor can value work that isn't to spec at less than full price. A court called this an "appropriate deduction" (Mul v Hutton Construction, 2014). Even then, the lower figure must go through a valid notice.
Your reply, line by line
Don't argue the total. Take each line, accept what's fair, and dispute the rest with a reason. A short dated letter does more than ten phone calls.
| Charge | Ask for | Your usual answer |
|---|---|---|
| Cleaning | Dated photos, timesheets, who else was working there | Shared area: split it, or not ours |
| Damage | Photo before and after, who was in the area | No proof we caused it |
| Labour cover | Notice given to us, names, hours, rates | No notice, no chance to fix it |
| Delay | Programme, the delay event, the critical path | Delay caused by others or late information |
| Defects | Notice to remedy, cost of the fix | We were not given a chance to put it right |
Subject: Application [no.] — [project] — contra charges in your notice dated [date]
Your notice dated [date] deducts £[x] as contra charges. Please send, for each item: the subcontract clause relied on, the date we were notified, and the evidence and cost (photos, timesheets, invoices). We accept item [n] at £[x]. We do not accept items [n] and [n], because [reason]. Until the evidence is provided, we consider the balance of £[x] payable by [final date]. We reserve our rights, including to suspend performance and to refer the matter to adjudication.
Accepting a contra charge by staying quiet. If you don't reply, the next one will be bigger, and you'll have no record that you ever disputed the first.
Got a contra charge you think is wrong?
Book a free call and we'll look at the notice and your subcontract with you.
If they won't back down
Most contra charges settle once the main contractor sees you'll ask for evidence. If a large sum stays stuck, you have three options.
- Meet the QS or package manager on site with your photos and records. Agree a split on shared items.
- Carry the disputed sum into your next application with your evidence attached, so it stays live.
- Adjudication for sums that matter. You can refer at any time; the adjudicator decides within 28 days of referral.
If the money isn't paid at all, read what to do when a main contractor isn't paying: interest, suspension and when to adjudicate. If the deduction came in a pay less notice, check it with our pay less notice 7-day plan.
Stop the next contra charge before it starts
Contra charges are cheapest to fight before the job starts. These are the terms we'd want if we were the subcontractor.
- No charge without notice: written notice of the problem and a reasonable time to put it right first.
- Evidence with every charge: photos, timesheets and invoices attached to the notice.
- A cap or a rate: agreed day rates for labour cover, not whatever the main contractor's agency charges.
- Shared areas split: cleaning and protection costs shared between trades by agreement.
On site, protect yourself with records. Take dated photos at the start and end of each visit. Get signed handovers when you finish an area, and every instruction in writing. Our guide on how to write a payment application shows how to back each one up.
This is the paperwork our commercial management service runs for contractors. Joe Crawford, Craftex's Commercial Director, has 37+ years in commercial construction. To get your subcontracts and applications set up so deductions stay rare, book a free strategy call.
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Get the free guideThis is general information on the rules in England and Wales as of October 2026, not legal advice. For a large or disputed sum, speak to a construction solicitor.
Before you sign the next subcontract
- The contra charge clause needs notice and a chance to fix it first
- Labour cover is at an agreed day rate
- You photograph every area at the start and end of each visit
- You reply to every deduction in writing within 48 hours
- You know your payment dates and the pay less deadline
