CIS registration does not determine employment status

One of the most common and costly mistakes in construction is assuming that because someone is CIS-registered, they are automatically self-employed. This is wrong. CIS registration and employment status are completely separate legal concepts.

Getting this wrong can result in:

• For contractors: National Insurance demands, penalties, tribunal claims, and back-payment of employee rights
• For workers: Loss of employment protections and benefits you should have had

This guide explains the distinction and helps you avoid these costly errors.

What CIS actually does

The Construction Industry Scheme is purely a tax collection mechanism. It requires contractors to deduct tax from payments to subcontractors and send it to HMRC. That is all it does.

The employment status tests

Employment status is determined by how the working relationship actually operates, not by what the parties call it or which tax scheme applies. Courts and tribunals look at multiple factors:

Key indicators of self-employment (genuine business)

• Substitution: Can send a replacement without the contractor's approval
• Financial risk: Bears risk of loss on contracts (fixed price, own insurance)
• Equipment: Provides significant tools, equipment, or materials
• Control: Decides how, when, and where to do the work
• Multiple clients: Works for several contractors, not just one
• Business structure: Has business premises, marketing, own staff

Key indicators of employment (disguised employee)

• Control: Contractor dictates working hours, methods, and location
• Mutuality: Ongoing obligation to offer work and accept it
• Integration: Works alongside employees, same supervision
• Exclusivity: Works only or mainly for one contractor
• Equipment: Uses contractor's tools and equipment
• Payment: Regular weekly or monthly payments regardless of output

Using the CEST tool

HMRC provides the Check Employment Status for Tax (CEST) tool to help determine employment status. While not legally binding, HMRC will stand by the result if:

• You enter accurate and complete information
• It reflects the actual working arrangement (not just what the contract says)
• The arrangement does not change after the assessment

Best practice: Complete CEST for each engagement and keep the result on file. If challenged, this demonstrates you took reasonable care to determine status correctly.

Risks of misclassification for contractors

If HMRC or an employment tribunal determines that a CIS-registered worker was actually an employee, the contractor faces serious consequences:

Tax and National Insurance

• Employer NI: 15% on all earnings above the secondary threshold (5,000 pounds a year, rates from 6 April 2025) - backdated up to 6 years
• Employee NI: May need to pay the employee's share if not recoverable
• Interest: On all late-paid tax and NI
• Penalties: Up to 100% of the tax due for careless or deliberate errors

Employment rights claims

• Holiday pay: 5.6 weeks per year, potentially years of unpaid entitlement
• Minimum wage: If effective hourly rate was below NMW after recalculation
• Sick pay: Statutory Sick Pay if they were off sick
• Unfair dismissal: If worked 2+ years and terminated
• Redundancy pay: If work ended and they had 2+ years service
• Pension auto-enrolment: Employer contributions should have been made

Total exposure example: A worker misclassified for 3 years on 40,000 pounds annual payments could result in: around 15,750 pounds employer NI (15% on earnings above the 5,000 pound threshold, 5,250 pounds per year) + 6,700 pounds holiday pay + pension contributions + interest + penalties. Total exposure could exceed 30,000 pounds per worker.

Risks for workers

Workers also face risks if they accept CIS treatment when they should be employees:

• No Statutory Sick Pay when ill
• No holiday pay - must fund own time off
• No redundancy if work ends
• No unfair dismissal protection
• No employer pension contributions
• Personal liability for Class 4 NI instead of employee Class 1 (compulsory Class 2 NI was abolished from 6 April 2024)

IR35 and CIS - when both apply

The off-payroll working rules (IR35) apply when a worker provides services through their own limited company. In construction, the two regimes interact:

• Medium and large contractors must assess employment status under the off-payroll rules (Chapter 10 of Part 2 of ITEPA 2003)
• If the engagement is "inside IR35" (deemed employment), PAYE must be operated on the deemed direct payment
• Where the off-payroll rules apply and PAYE is operated, CIS does not apply to that payment - you do not make a CIS deduction on top of PAYE
• Small company exemption: If the client meets 2 of 3 thresholds (turnover under 15 million pounds, balance sheet under 7.5 million pounds, under 50 employees - thresholds raised from 10.2 million/5.1 million for off-payroll purposes from 6 April 2026), the contractor determines their own status under Chapter 8. Because size is tested on the previous financial year, the practical shift for many clients takes effect from April 2027

Best practice for contractors

To protect your business from misclassification claims:

1. Assess each engagement individually - do not assume CIS registration means self-employment. Status depends on how the relationship actually works.
2. Use the CEST tool - document your determination for each worker and keep the result on file.
3. Review contracts against reality - a contract saying "self-employed" means nothing if the actual working practices indicate employment.
4. Monitor for changes - status can change if working practices change. An arrangement that starts as self-employment can become employment over time.
5. Keep detailed records - document why you treated someone as self-employed, including evidence of their other clients, equipment, and risk-bearing.
6. Take professional advice - for borderline cases, get specialist employment status advice before starting the engagement.

When to use PAYE instead of CIS

If your assessment indicates the worker is actually an employee, you must:

• Register as an employer with HMRC (if not already)
• Put the worker on PAYE payroll
• Deduct Income Tax and employee NI
• Pay employer NI
• Enrol them in your workplace pension
• Provide employment rights (contracts, holiday, sick pay, etc.)

Do not use CIS for someone who should be on PAYE. The penalties for wrong classification are far higher than the administrative cost of doing it correctly.

Common scenarios

Scenario 1: The regular labourer

Situation: A labourer works for you every week, uses your tools, works your hours, and has done so for 2 years.

Assessment: Almost certainly an employee. The regularity, control, and integration all point to employment. CIS treatment is incorrect - use PAYE.

Scenario 2: The specialist subcontractor

Situation: An electrician does a job for you. They have their own van, tools, insurance, work for multiple contractors, and quote fixed prices.

Assessment: Likely genuinely self-employed. CIS treatment is correct.

Scenario 3: The one-man band on long contract

Situation: A sole trader plasterer works on your site 5 days a week for 6 months. They use their own tools but work your hours and take direction from your foreman.

Assessment: Borderline. Use CEST tool and document carefully. The control and integration suggest employment despite having own tools.

Related guides

• Register as a CIS contractor - how to register and your ongoing obligations
• Verify a subcontractor's CIS status - checking verification before payment
• Construction tax compliance overview - how CIS, VAT, CITB, and PAYE work together
• VAT reverse charge for construction - when to apply the reverse charge