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ContractorsUpdated 2026-02-12

What is the Construction Industry Scheme (CIS)?

Quick Answer

CIS is a tax deduction scheme where contractors deduct tax from payments to subcontractors. Standard deduction is 20%, or 30% for unregistered subcontractors. Some get 0% (gross payment status).

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Detailed Explanation

Construction Industry Scheme (CIS)

Who it applies to

- Contractors paying for construction work - Subcontractors receiving payments for construction work - Includes: building, repairs, decorating, demolition, civil engineering

Contractor obligations

- Register as a contractor with HMRC - Verify subcontractors before paying - Deduct tax from payments (labour element) - File monthly CIS returns - Keep records for 3 years

Deduction rates

- 20%: Registered subcontractors - 30%: Unregistered subcontractors - 0%: Gross payment status (strict criteria)

Gross payment status requirements

- Pass compliance test (filed returns, paid tax) - Pass turnover test (£30,000+ for sole traders) - Pass business test (in construction for 3+ years or directors with experience)

What's deducted

- Tax on labour costs only - Materials cost is paid gross - Must show materials separately on invoices

Subcontractor recovery

- CIS deductions count as tax paid - Set against Corporation Tax or PAYE liability - Claim refund if overpaid

Common mistakes

- Not verifying subcontractors - Deducting from materials - Late CIS returns (£100 penalty per month) - Miscategorizing employees as subcontractors

Filing

- Monthly returns by 19th (22nd if online) - Include all payments to subcontractors - Nil returns required if no payments made

Source: HMRC Construction Industry Scheme

Real-World Examples

Plumbing Subcontractor

Sarah runs a plumbing business as a limited company and is subcontracted by a larger construction firm. As a registered subcontractor, the construction firm deducts 20% CIS tax from Sarah's invoices, covering the labour element, before paying her the remaining balance.

Property Developer as Contractor

ABC Developers Ltd. hires various subcontractors (electricians, carpenters, bricklayers) for a new housing development. ABC Developers must register as a contractor, verify each subcontractor's CIS status with HMRC, and deduct the correct CIS tax before making payments.

Landscaper with Gross Payment Status

John's landscaping company meets HMRC's criteria for Gross Payment Status. He's subcontracted for a large commercial development. Because of his GPS, the main contractor doesn't deduct any CIS tax from his invoices, and John handles his tax obligations directly with HMRC.

Common Mistakes to Avoid

  • Failing to register as a contractor when obligated, resulting in penalties from HMRC.
  • Incorrectly classifying materials vs. labour on invoices, leading to inaccurate CIS deductions.
  • Not verifying a subcontractor's CIS registration status before payment and assuming a 20% deduction is always correct.
  • Neglecting to keep accurate records of CIS payments and deductions for at least three years, hindering accurate reporting to HMRC.

What qualifies as 'construction work' under the CIS?

Construction work is broadly defined and includes activities like building, alterations, repairs, demolition, and even painting and decorating. HMRC provides a detailed list of included and excluded activities in their CIS guidance notes.

How does CIS affect my VAT obligations?

CIS deductions are made *before* VAT is added to the invoice. You still need to charge VAT on the full invoice amount and account for it separately in your VAT returns, regardless of CIS deductions.

What happens if I'm both a contractor and a subcontractor?

If your company operates as both, you must fulfill both the contractor and subcontractor obligations under CIS. You'll deduct CIS from your subcontractors and have CIS deducted from your payments as a subcontractor.

How do I apply for Gross Payment Status?

You can apply for Gross Payment Status through HMRC's online services. You'll need to meet certain criteria, including a good tax payment history and a proven record of compliance with CIS regulations.

Practical Tips

  • Use accounting software that integrates with CIS to automate subcontractor verification and CIS return preparation.
  • Create a template invoice clearly separating labour and materials costs to ensure accurate CIS deductions.
  • Implement a system for regularly checking subcontractor CIS registration status to avoid over or under-deducting CIS tax.
  • Set calendar reminders for monthly CIS return deadlines to avoid late filing penalties from HMRC. The deadline is the 19th of each month for the previous tax month.

Related Questions

What is IR35?

IR35 is legislation that determines whether a contractor is genuinely self-employed or should be taxed as an employee. If IR35 applies, you pay similar taxes to an employee.

Browse all questions →

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