How much CIS could you get back? Estimate it in two minutes.
Contractors must take 20% off payments to you if you’re registered for CIS (30% if you’re not). That money counts towards your tax bill. If more was taken than you owe, the difference comes back to you from HMRC.
Tax years covered: 2025-26 and 2026-27. Earlier years are not covered yet. The estimator runs in this browser tab: nothing you type into it is sent to us.
Your figures
What the estimate assumes
- Your CIS work is your only income in the year: no wages, pension, rent or other income.
- The Income Tax rates for England, Wales and Northern Ireland, or Scotland’s if you tick “I live in Scotland” (2025-26 and 2026-27). Class 4 National Insurance is the same across the UK.
- The range shows your refund if your expenses come out 10% lower or 10% higher than you entered, because first figures are usually rough.
- A van or car is claimed one way: its running costs, or its business miles at the flat rate. Not both for the same vehicle, and only the business share of anything you also use privately.
- Under the cash basis, the cost of equipment bought to keep and use in the business, such as machinery, computers and vans, is claimed as a normal allowable expense rather than a capital allowance. Cars are different: they go through capital allowances. If you bought a van this year, add its cost under other costs to see the difference, unless you claim its miles at the flat rate.
- Not included: student loan repayments, payments on account, losses from earlier years, and any tax you still owe from earlier years.
Ten worked examples (2026-27)
Each row assumes CIS is the person’s only income and uses the 2026-27 rates for England, Wales and Northern Ireland.
| Example | Gross pay | Expenses | CIS taken | Tax and Class 4 due | Estimate |
|---|---|---|---|---|---|
| Electrician, registered (20%), basic-rate profit | £30,000 | £5,000 | £6,000 | £3,231.80 | £2,768.20 back |
| Plasterer, part-year work | £20,000 | £2,000 | £4,000 | £1,411.80 | £2,588.20 back |
| Joiner with van and tool costs | £45,000 | £8,000 | £9,000 | £6,351.80 | £2,648.20 back |
| Bricklayer, profit just under the higher-rate line | £60,000 | £10,000 | £12,000 | £9,731.80 | £2,268.20 back |
| Groundworker into higher rate — owes a balance | £70,000 | £5,000 | £14,000 | £15,988.60 | £1,988.60 to pay |
| Labourer not registered for CIS (30%) | £25,000 | £3,000 | £7,500 | £2,451.80 | £5,048.20 back |
| Apprentice-level profit under the Personal Allowance | £12,000 | £1,500 | £2,400 | £0 | £2,400 back |
| Roofer with gross payment status (no deductions) | £40,000 | £5,000 | £0 | £5,831.80 | £5,831.80 to pay |
| Site manager over £100,000 — allowance tapered | £120,000 | £10,000 | £24,000 | £36,888.60 | £12,888.60 to pay |
| Specialist contractor into additional rate | £160,000 | £10,000 | £32,000 | £57,959.60 | £25,959.60 to pay |
Voice and visuals made with automated software, including AI.
How the estimate works
- Expenses = your van running costs or your business miles at the flat rate (45p a mile for the first 10,000 miles, then 25p, in 2025-26; 55p a mile for the first 10,000 miles, then 25p, in 2026-27), plus tools, phone, workwear, materials and other costs.
- Profit = gross pay minus expenses.
- Income Tax on profit above your Personal Allowance (£12,570, reduced by £1 for every £2 of income over £100,000 in 2025-26 and 2026-27), at the Scottish bands if you tick “I live in Scotland” (2025-26 and 2026-27).
- Class 4 National Insurance (6% between £12,570 and £50,270, and 2% above in 2025-26 and 2026-27).
- Estimate = CIS deducted minus the tax and Class 4 due. A positive figure is what you could get back. It can never be more than the CIS taken.
- Range = the same sum with your expenses 10% lower and 10% higher.
What the estimate assumes
- Your CIS work is your only income in the year: no wages, pension, rent or other income.
- The Income Tax rates for England, Wales and Northern Ireland, or Scotland’s if you tick “I live in Scotland” (2025-26 and 2026-27). Class 4 National Insurance is the same across the UK.
- The range shows your refund if your expenses come out 10% lower or 10% higher than you entered, because first figures are usually rough.
- A van or car is claimed one way: its running costs, or its business miles at the flat rate. Not both for the same vehicle, and only the business share of anything you also use privately.
- Under the cash basis, the cost of equipment bought to keep and use in the business, such as machinery, computers and vans, is claimed as a normal allowable expense rather than a capital allowance. Cars are different: they go through capital allowances. If you bought a van this year, add its cost under other costs to see the difference, unless you claim its miles at the flat rate.
- Not included: student loan repayments, payments on account, losses from earlier years, and any tax you still owe from earlier years.
Get a reminder to claim it back
We’ll email you after 5 April, when you can file and claim your CIS back.
Questions people ask
How do I claim my CIS deductions back?
A sole-trader subcontractor gets over-deducted CIS back by entering gross pay as income and total deductions as CIS deductions on the Self Assessment return; HMRC deducts them from the bill and repays any excess. Before you join Making Tax Digital, over-deducted CIS is claimed back through your Self Assessment tax return. Once you are in Making Tax Digital, HMRC adds your CIS deductions to your tax return, and any refund is requested separately through HMRC online services. Either way, the sooner after 5 April the return is filed, the sooner HMRC can repay you.
How long does the repayment take?
HMRC's SA100 asks taxpayers to allow up to 4 weeks for a repayment to reach them before contacting HMRC.
What rate should contractors deduct?
20% if you’re registered for CIS, 30% if you’re not, and nothing if you have gross payment status.
Does this work if I live in Scotland?
Yes, for 2025-26 and 2026-27: tick “I live in Scotland” and Income Tax uses the Scottish bands and rates. CIS deductions and Class 4 National Insurance are the same across the UK. Scottish Income Tax depends on where your main home is, not where you work.
What doesn’t this estimate include?
Other income such as wages or rent, student loan repayments, payments on account, and losses from earlier years. Any of these can change your figure.
This is an estimate based on the figures you entered and the rules for 2026-27. Your actual figure may differ.
What happens next
- Gather your monthly CIS statements and your receipts for the year.
- File your tax return soon after 5 April — the sooner you file, the sooner HMRC can repay you.
- Or join the Trades Tax waitlist and we’ll match your statements and count your deductions in your tax return.
Rather not do it yourself?
With Trades Tax we keep your books from your bank statements and file every quarterly update and your tax return: CIS deductions matched to your statements and counted in your tax return, with any refund requested from HMRC. You confirm every figure before it’s sent.
Founding offer, first 500 trades clients: £5 a month for your first 3 months, then £35 a month. Cancel any time. We’ll remind you before it changes. Prices include VAT. No payment is taken while you wait.
Hold your place on the trades waitlist
We’ll email you when Trades Tax opens, with the founding offer while places last. No payment is taken.
Sources
- What you must do as a Construction Industry Scheme (CIS) subcontractor — checked 15 October 2026
- What you must do as a CIS subcontractor: Pay tax and claim back deductions — checked 15 October 2026
- SA100 2026 Tax return — checked 15 October 2026
- Income Tax rates and allowances for current and previous tax years — checked 17 October 2026
- Income Tax in Scotland: 2025 to 2026 tax year — checked 19 October 2026
- Rates and allowances: National Insurance contributions — checked 17 October 2026
- Simplified expenses if you're self-employed: Vehicles — checked 17 October 2026
- Income Tax rates and Personal Allowances — checked 15 October 2026
- Income Tax in Scotland — checked 17 October 2026
- Self-employed National Insurance rates — checked 15 October 2026
- Simpler income tax: cash basis — checked 17 October 2026