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CIS deduction calculator

Work out the CIS deduction and the net payment on a subcontractor's invoice, following HMRC's method: take off VAT, materials and the other allowed costs, then apply 20%, 30% or 0%.

How it works

HMRC says to start with the subcontractor's gross invoice, take off VAT, materials they paid for directly, consumable stores, fuel (except for travelling), plant hire for the job and manufacturing or prefabricating materials, then deduct the CIS rate HMRC gave you when you verified them (GOV.UK). If there's no evidence of materials costs, HMRC says to estimate them.

For a subcontractor, the same sums show what you'll receive. The deduction counts towards your tax and National Insurance. Related: quote and VAT calculator, invoicing apps for builders.

Questions

Do I deduct CIS from materials?

No. Take off materials the subcontractor paid for directly, as well as VAT, plant hire, consumables and fuel, before applying the rate. See GOV.UK.

Who decides the rate?

HMRC tells you the rate when you verify the subcontractor: 20% if they're registered, 30% if not, and 0% with gross payment status.

Is this tax advice?

No. It applies HMRC's published method, but check unusual cases with HMRC or an accountant.