Take VAT and the subcontractor's own costs (materials they bought, plant hire, fuel not for travel, consumables) off the invoice, then apply the rate HMRC gave you: 20% if they are registered, 30% if not, nothing if they have gross payment status.
Free, with no sign-up. Everything is worked out in your browser: nothing you type is sent to us or stored. A guide, not tax advice. Based on GOV.UK guidance checked on 31 October 2026. Use the rate HMRC gave you when you verified the subcontractor.
The deduction is never on the whole invoice unless the whole invoice is labour. Here is a registered subcontractor's invoice worked through.
| Invoice, excluding VAT | £5,000 |
|---|---|
| Less what the subcontractor paid for | £1,500 |
| The rate applies to | £3,500 |
| CIS deduction at 20% | £700 |
| VAT on the invoice | £1,000 |
| Pay the subcontractor | £5,300 |
Change the figures in the calculator to match your own invoice.
Enter the invoice as the subcontractor sent it. Leave a box empty if it does not apply.
Fuel only counts when it is not for travel. Ask for receipts for materials; if there are none, HMRC says to estimate their cost. Give the subcontractor a payment and deduction statement within 14 days of the end of each tax month.
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