CIS For UK Tradesmen: How It Works And What You Need To Know

Quick Answer

Under CIS, a contractor may deduct money from a subcontractor’s payment for construction work and pass that deduction to HMRC as an advance toward the subcontractor’s tax. Verify the subcontractor, use HMRC’s rate, exclude the right materials amounts, give a payment statement, then file the monthly return on time. This is general information, not tax advice. Check current rules on GOV.UK or with your accountant.

Introduction

If you pay subcontractors for construction work, or you get paid as a subcontractor, you may need to deal with the Construction Industry Scheme. It can feel messy the first time you meet it, especially alongside materials, VAT and reverse charge.

This guide covers the main ideas in plain English. For the invoice habits that keep CIS paperwork tidy day to day, see CIS invoices for subcontractors.

What Is CIS?

A contractor may deduct an amount from a subcontractor’s payment and send that deduction to HMRC. For the subcontractor it is usually an advance toward tax and National Insurance, not an extra fee on top of the job.

Contractor: the business paying for construction work.

Subcontractor: the business or person carrying out that work.

Many trade firms are both. You might work as a subcontractor on one project and hire another trade on the next.

Does CIS Apply To Every Job?

No. CIS depends on the work and the relationship. A homeowner hiring a tradesperson for their own home is not normally a CIS contractor. A construction business paying a subcontractor for covered work may have CIS duties.

Do not decide from the trade name alone. Check the work and contract against HMRC guidance when you are unsure.

Registration And Deduction Rates

Contractors register for CIS when they meet the rules for paying subcontractors for construction work. Subcontractors should register too. An unregistered subcontractor can still be paid, but the deduction rate is usually higher.

After verification, HMRC tells the contractor which rate to use. In broad terms that is often 20% for a registered verified subcontractor, 30% if not registered or not verified at the registered rate, and 0% with gross payment status. Always use the rate HMRC returns, not a rate the subcontractor quotes from memory.

Gross payment status means no CIS deduction on that payment. It does not mean the income is tax free.

How A Deduction Is Calculated

A common mistake is taking the CIS percentage from the full invoice total. Work out the amount subject to deduction first. VAT and certain materials amounts are handled separately under HMRC rules.

Simple example with no VAT: labour £1,000 and qualifying materials £200 on a £1,200 invoice. If the rate is 20% on the labour amount, the deduction is £200, the subcontractor receives £1,000 for labour plus the materials amount, and £200 goes to HMRC. Real invoices can be more complex, so keep materials evidence and ask your accountant when the split is unclear.

What Contractors Need To Do

1. Register as a CIS contractor when required
2. Confirm the work is inside the scheme
3. Check employment status. Calling someone self employed does not settle it
4. Verify the subcontractor and use HMRC’s rate
5. Calculate and make any deduction when paying
6. Give a payment and deduction statement when you deduct
7. File the monthly CIS return and pay deductions on time
8. Keep invoices, materials notes, verification, payments and statements together

Returns, Statements And Timing

CIS tax months run from the 6th of one month to the 5th of the next. Monthly returns are normally due by the 19th after that period ends. Payment deadlines for deductions are separate, so check the current HMRC dates for electronic and postal payments.

When you make a deduction, give the subcontractor a written payment and deduction statement within the required time. If you are the subcontractor, keep every statement. You will need those figures when you report income and claim credit for deductions.

CIS Is Not VAT Reverse Charge

CIS is about deductions from certain construction payments. The VAT domestic reverse charge is about who accounts for VAT on certain business to business construction services. Both can appear on related work, but one does not automatically answer the other. See also VAT on quotes and invoices for tradesmen.

How Software Helps

Total Tradesmen keeps the job, invoice lines and payment trail connected so CIS related work is easier to review with your accountant. Job management does not replace HMRC filing software or professional advice, but organised invoices and materials notes stop CIS admin becoming a scavenger hunt.

FAQs

Can I be a contractor and a subcontractor?

Yes. Many businesses sit in both roles on different jobs. Keep the paperwork clear for each relationship.

Do materials always escape CIS deduction?

Only where HMRC’s rules allow the exclusion and you can support what was paid for materials. Guessing creates problems later.

Where should I check the latest rules?

Start with GOV.UK on CIS and speak to your accountant for your own jobs.

Conclusion

CIS is manageable when you know the roles, verify properly, calculate deductions carefully and keep statements and returns on time. Keep job and invoice records tidy, then let your accountant and HMRC compatible process handle the formal side.