A CIS tax rebate is the refund HMRC pays when the 20% or 30% deducted from your construction pay is more than the Income Tax and National Insurance you actually owe. You claim it through your Self Assessment return.
If you work as a subcontractor in UK construction, HMRC has probably taken more tax than you owe. The Construction Industry Scheme deducts 20% from most registered subcontractors, and 30% if you are not registered.
Those deductions ignore your expenses, allowances and personal circumstances, so many subcontractors are owed a CIS tax rebate at the end of the tax year.
At R&R Chartered Certified Accountants, we help subcontractors across Lancashire and the North West claim back what they are owed. This guide explains how rebates work, what you can claim and the simplest way to get your money back.
If you would prefer someone to check the numbers and file it for you, our CIS accountant service does exactly that, as part of the wider support we give construction and engineering businesses.
What Is a CIS Tax Rebate?
A CIS tax rebate is a refund from HMRC when the tax deducted from your construction payments is more than your final income tax and National Insurance liability. The rebate is calculated when you file your annual self assessment tax return.
Illustrative example: a subcontractor earns £30,000 in labour payments and has 20% deducted under CIS, so HMRC receives £6,000 during the year.
After the personal allowance and allowable expenses, the actual tax bill might be only £2,500. In this simplified example, the difference would be refunded as a rebate.
Who Can Claim a CIS Rebate?
You can claim a CIS rebate if:
- You worked as a subcontractor under the Construction Industry Scheme during the tax year.
- Tax was deducted from your payments by contractors.
- You have overpaid tax once your income, expenses and allowances are taken into account.
Most subcontractors who work regularly under CIS are due some money back, especially if they have significant travel, tools or home office costs.
What Can You Claim Against CIS Income?
Allowable expenses reduce your taxable profit, so every legitimate cost you record increases the rebate.
For most subcontractors the biggest are mileage, tools, protective clothing, insurance and phone costs. Our CIS subcontractor guide lists what you can and cannot claim in full.
Good record keeping is essential. HMRC may ask to see receipts, invoices, bank statements and mileage logs.
How Do You Claim a CIS Tax Rebate?
The claim is made through your self assessment tax return. The steps are:
- Gather all your CIS payment and deduction statements from contractors.
- Collect receipts and records for all allowable expenses.
- Complete your self assessment tax return, entering your CIS deductions in the correct section.
- Submit the return online before the 31 January deadline.
- Wait for HMRC to process the return and issue the refund. HMRC does not publish a fixed timescale.
A CIS accountant can handle the whole process and check that nothing is missed.
How Long Does a CIS Rebate Take?
HMRC does not publish a fixed timescale for CIS rebates.
HMRC checks your deductions against the monthly returns your contractors file, so a missing or mismatched contractor return can hold it up. The Where’s my reply tool in your HMRC online account shows the expected date.
Delays can also happen if HMRC asks for more evidence, if your CIS statements don’t match, or during busy periods such as January and April.
Filing early, keeping clear records and making sure your figures match HMRC’s records all help avoid delays.
Refunds are processed through your Self Assessment return, and HMRC explains repayment timescales in its Self Assessment guidance on GOV.UK. You can also check what you owe or are owed in your HMRC personal tax account.
Frequently Asked Questions
Yes. Your self assessment return covers all your income, including employment and self-employment. CIS deductions are still refundable if you have overpaid overall.
You can request copies from your contractors or check your HMRC online account, which should show the deductions reported. An accountant can also help reconcile missing statements.
You can file the return yourself, but an accountant usually increases the rebate by claiming expenses you might miss and reduces the risk of HMRC enquiries.
You claim the rebate through your self assessment tax return, which is due by 31 January following the end of the tax year. The sooner you file, the sooner HMRC pays.
Yes, if you missed a year. You can usually amend a tax return within one year of the original filing deadline. For an earlier year, you have four years from the end of that tax year to claim, so a 2022/23 refund must be claimed by 5 April 2027.
The Bottom Line
CIS tax rebates are one of the main rewards for staying organised as a subcontractor. If tax has been deducted from your construction pay, you are very likely owed money back.
The key is an accurate Self Assessment return that includes every allowable expense.
If you want help claiming your CIS rebate, contact R&R Chartered Certified Accountants for a free review. We will check your CIS statements, identify your allowable expenses and make sure you claim the full rebate you are owed.
Tax figures checked by Rehan Razzaq FCCA on 8 October 2026 for the 2026/27 tax year.
This article is general guidance for UK businesses and individuals and does not constitute personal financial or tax advice. Rules, thresholds and individual circumstances vary — always confirm your specific position with a qualified accountant before acting.
Rehan Razzaq, FCCA
Founder, R&R Chartered Certified Accountants
ACCA Chartered Certified and Xero Certified Advisor, helping UK small businesses and subcontractors with accounts, tax and financial planning since 2021.
We work with clients right across Lancashire and the North West. If you are looking for accountants in Blackburn, or a local accountant in Nelson or accountant in Accrington, our team is a short drive away.
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