CIS Tax Refunds for Roofers
Written and reviewed by the Roofer Accountants editorial team. Last reviewed 29 July 2026.
If you are a self-employed roofer working under CIS, there is a good chance HMRC owes you money, and has done every year you have been subcontracting. The 20% taken from your payments is almost always more than your real tax, and the overpayment comes back as a refund.
This is why roofers so often overpay, roughly how big the gap tends to be, and how the refund is actually claimed.
Why Roofers Overpay
The CIS deduction is blunt by design. A contractor takes 20% of your labour and sends it to HMRC without knowing anything about your costs or your personal allowance. Your real tax, though, is worked out on your profit: your labour income less your van, tools, materials, insurance, protective kit and everything else it takes to run a roofing round.
A roofer with real expenses and the tax-free £12,570 personal allowance nearly always has a true tax bill well below the 20% that was held back. That gap is your refund, and for a roofer with a full year of deductions it is often the single biggest cheque of the year.
What Makes the Refund Bigger
The refund grows with every legitimate expense you claim, because each one lowers the profit you are taxed on while the 20% was already taken on the full labour. Roofers routinely leave money on the table here by not claiming the van, the tools, the scaffold tower, the ladders, the protective wear and the phone.
Getting the expenses complete is the difference between a modest refund and the real one you are owed. It is also why a rushed, expenses-light return can quietly short-change you.
How the Refund Is Claimed
The refund comes through your Self Assessment tax return. We add up the CIS deducted across the year from your payment and deduction statements, set your income against your expenses and allowance to find the real tax, and the overpaid difference is repaid by HMRC, usually within a few weeks of filing.
You need the statements a contractor should give you for every payment, so keep them. Where they are missing, we can usually reconstruct the position from your bank and invoices. To claim what you are owed, send us your year.