Free IR35 Assessment Tool

IR35 Status Checker

Answer 7 questions to get an indication of whether your contract might be inside or outside IR35. Takes 2 minutes.

Based on HMRC CEST criteria | For guidance only

Important Disclaimer

This tool provides general guidance only and is not a substitute for professional advice. IR35 determinations are complex and depend on the specific facts of each engagement. Always consult a qualified tax professional.

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Control

Who decides how, when, and where the work is done?

HMRC looks at whether the client dictates your working hours, methods, location, and how you complete the work.

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Frequently Asked Questions About IR35

What is IR35?

IR35 is UK tax legislation designed to combat tax avoidance by workers supplying their services through an intermediary (like a limited company) who would be an employee if they contracted directly. If caught by IR35, you pay similar taxes to an employee but without employee benefits.

Who is responsible for determining IR35 status?

For medium and large private sector clients (and all public sector clients), the client is responsible for determining IR35 status. For small private sector clients, the contractor's own company remains responsible.

What happens if I'm inside IR35?

If inside IR35, you'll pay Income Tax and National Insurance similar to an employee. The fee-payer (usually an agency or client) must deduct these at source. You can still claim 5% of income as expenses.

What is the CEST tool?

CEST (Check Employment Status for Tax) is HMRC's official online tool to help determine IR35 status. While useful, many experts argue it doesn't cover all scenarios and recommend additional professional review for important contracts.

Can I appeal an inside IR35 decision?

Yes. If a client determines you're inside IR35, you have the right to challenge this. You should provide evidence of your actual working practices. If you disagree with HMRC's decision, you can appeal through the tax tribunal.

What evidence helps prove outside IR35 status?

Key evidence includes: a genuine right to substitute, control over how/when/where you work, working for multiple clients, having your own business premises and equipment, bearing financial risk, and not being integrated into the client's organisation.

Understanding IR35 for UK Contractors

IR35 is UK tax legislation that affects contractors working through their own limited companies. If HMRC determines you're "inside IR35," you're taxed similarly to an employee, paying Income Tax and National Insurance at source.

Key Factors HMRC Considers

The three main tests HMRC applies when determining IR35 status are:

  • Control: Does the client control how, when, and where the work is done?
  • Substitution: Can you genuinely send someone else to do the work?
  • Mutuality of Obligation: Is there an ongoing obligation to provide and accept work?

Off-Payroll Working Rules (IR35 Reform)

Since April 2021, medium and large private sector clients are responsible for determining the IR35 status of contractors. This shifted the liability from contractors to the hiring organisation.

Consequences of Being Inside IR35

If you're inside IR35, you'll pay roughly the same tax as an employee (Income Tax and National Insurance), but without employee benefits like holiday pay, sick pay, or pension contributions. The 5% expense allowance can help offset some costs.

Get Professional Advice

This checker provides guidance based on the key IR35 factors, but IR35 status depends on the specific facts of each contract. For important or high-value contracts, consider getting a formal IR35 review from a specialist.