Live calculator • Free • Nothing stored

CIS Tax & Refund Calculator

Enter your labour, materials and costs. We check the CIS that should have been taken, estimate your tax bill, and show whether you may be due a refund.

Private by designEverything runs in your browser.
Materials check includedFlags CIS that looks like it was taken on materials.
Working shownEvery figure in your estimate is broken down.
Example figures — replace with your own. Example figures are filled in so you can see how it works — replace them with your own before relying on the result shown.

1. Your setup

Choose the tax year and how your figures are entered.

Scottish bands differ and are not covered yet.

2. Labour, materials & CIS taken

Use totals from your CIS statements for the same period.

Labour only, excluding VAT — CIS is never taken on VAT.
Enter 0 or more for labour.
CIS should not be taken on materials.
Enter 0 or more for materials.
Same period as the figures above — total from your deduction statements.
Enter 0 or more for CIS deducted.

3. Allowable expenses

Same period as above. Don’t double-count fuel if you claim mileage below.

Excluding any mileage claim below.
Do not also claim the same fuel above.Enter 0 or more miles.

Estimate only — not tax advice. This calculator uses simplified UK rates for England, Wales & Northern Ireland, assumes materials cost equals materials reimbursed, and does not cover student loans, pension, other income, Scottish tax, limited companies (company CIS offset works differently), payments on account, voluntary Class 2 contributions, or CIS suffered in a different year. Your actual bill depends on your full Self Assessment. Verify with HMRC or a qualified accountant. No data is stored.