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CIS calculator

Work out the Construction Industry Scheme deduction on a bill, what the subcontractor is actually paid, and whether you’re due a refund at the end of the year. Nothing you type leaves your device.

Based on GOV.UK guidance, last checked 29 October 2026 · An estimate, not tax advice

Work out a CIS deduction

Which amount do you have? The labour amount before CISWhat I was paid for labour after CIS

Labour The work itself, excluding VAT

£

Materials Optional: materials the subcontractor bought for the job. No CIS is taken off these

£

Subcontractor’s CIS status Registered for CIS (20%)Not registered (30%)Gross payment status (0%)

Work out the deduction

Estimate your CIS refund

Most subcontractors have more taken off through CIS than they owe, because the deduction ignores your personal allowance and expenses. Enter your figures for the 2026/27 tax year.

Your profit for the year All your income before CIS deductions, minus allowable expenses (tools, van, materials, phone and so on)

£

Total CIS deducted in the year Add up your monthly payment and deduction statements

£

Where do you live? England, Wales or Northern IrelandScotland

Estimate my refund

How CIS deductions work

• Contractors take 20% off a registered subcontractor’s labour, 30% if they aren’t registered, and nothing if they have gross payment status.
• The deduction is only on labour. Materials, VAT and equipment hire for the job are left out.
• The contractor pays the deductions to HMRC and gives you a payment and deduction statement each month.
• At the end of the tax year you send a Self Assessment return. The deductions count towards your tax and Class 4 National Insurance, and any overpayment is refunded.

Example: a registered subcontractor bills £1,000 labour and £400 materials. The contractor takes 20% of £1,000, so £200, and pays £1,200.

Read more in our CIS guide. Sources: What is the Construction Industry Scheme and What you must do as a CIS subcontractor on GOV.UK.