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CIS Deduction Calculator

Labour, materials, your rate — and you'll see exactly what lands in your account. Deduction applies to labour only, never materials.

Labour (ex VAT)
£
Materials (ex VAT, at cost)
£
Your CIS rate
20%
CIS registered
30%
Not registered
0%
Gross status
Invoice total (labour + materials)£0.00
CIS deduction (20% of labour)−£0.00
You get paid£0.00
The deduction isn't lost — it's an advance on your tax. Sole traders reconcile it through Self Assessment; companies offset it against PAYE.
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Correct labour/materials split, deduction shown, PDF ready to send. No sign-up.

How the CIS deduction works

Under the Construction Industry Scheme, contractors deduct money from a subcontractor's payments and pass it to HMRC as an advance on the subcontractor's tax and National Insurance. The deduction applies to the labour element only — genuine material costs, plant hire you paid for, and VAT are excluded.

The rate depends on your status with HMRC: 20% if you're registered for CIS, 30% if you're not registered or couldn't be verified, and 0% if you hold gross payment status. On the maths above: deduction = labour × rate, and you're paid labour + materials − deduction.

New to CIS or explaining it to your crew? Read our plain-English guide — Get your UTR → What you can claim → How to invoice → CIS explained: why 20% leaves your pay, and how to get it back — also available in Română, Polski, Български, Українська, Español and Português.

Quick answers

Is the CIS deduction taken from materials?

No. CIS applies to labour only. Genuine material costs — supplied at cost, with receipts — are paid in full. That's why splitting labour and materials on your invoice matters.

Why am I deducted 30% instead of 20%?

30% applies when you're not CIS-registered, or the contractor couldn't verify you with HMRC. Registering brings it to 20%. A mismatched name or UTR at verification is a common cause — check what details the contractor used.

Is CIS calculated before or after VAT?

On amounts excluding VAT. On most construction-to-construction invoices VAT isn't charged anyway — the domestic reverse charge means the customer accounts for it.

Do I get the deduction back?

It's an advance on your tax, not a cost. Sole traders reconcile through Self Assessment — overpaid amounts come back as a refund. Limited companies offset against PAYE or claim after year end.

What is gross payment status (0%)?

HMRC pays-you-in-full status: no deductions, you settle your own tax. You qualify by passing turnover, business and compliance tests — at least £30,000 turnover for a sole trader.

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This calculator is a guide, not tax advice — check your position with HMRC or your accountant.
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