IR35 Status Checker for UK Contractors
Answer 7 questions about your contract and working practices to find out if you are likely inside or outside IR35. Free, instant, no sign-up.
1.Can you send a substitute to do the work instead of you?
Does your contract allow you to send someone else to do the work, and would your client accept this?
2.Do you control how, when, and where you work?
Can you decide your own working hours and methods, rather than being directed by the client?
3.Can you turn down work, and is the client free to offer you none?
Mutuality of Obligation: there should be no expectation that the client must offer work or that you must accept it.
4.Do you use your own equipment and tools to do the work?
Does the client provide you with a computer, desk space, or other resources as if you were an employee?
5.Do you bear financial risk? (e.g. fixing mistakes at your own cost)
Would you have to put things right at your own expense if you did the work incorrectly? Do you invoice for a fixed deliverable rather than time?
6.Are you free to work for other clients at the same time?
Working exclusively for one client for an extended period is a strong indicator of employment.
7.Are you clearly separate from the client's organisation?
Do you avoid being integrated into the client's team — e.g. not attending internal meetings, not having a company email, not being managed as a member of staff?
What is IR35?
IR35 — formally known as the off-payroll working rules — is UK legislation introduced in 2000 to tackle “disguised employment”. It targets contractors who work through a limited company but operate in a way that is effectively identical to being an employee of their client.
If HMRC determines that you fall inside IR35, you must pay income tax and National Insurance on your contract income as if you were a PAYE employee — even if you work through your own limited company. This can significantly reduce your take-home pay.
The three key IR35 tests
1. Substitution
Can you send a substitute to do the work in your place? A genuine contractor can. An employee cannot. Your contract should allow substitution, and it should be a real right — not just words on paper.
2. Control
Does the client control what you do, how you do it, when you work, and where you work? High client control is a strong indicator of employment. Genuine contractors have autonomy over their working methods.
3. Mutuality of Obligation (MOO)
Is the client obliged to offer you work, and are you obliged to accept it? Employees work under a continuous obligation. Genuine contractors are engaged for a specific project — neither party is obliged to continue.
Other factors HMRC considers
- •Financial risk: Do you bear financial risk, such as correcting mistakes at your own cost, or pricing a fixed deliverable?
- •Part and parcel: Are you integrated into the client's organisation — attending internal meetings, having a company email, being managed as staff?
- •Equipment: Do you use your own equipment, or does the client provide everything as they would for an employee?
- •Exclusivity: Are you free to work for other clients? Exclusivity is a strong indicator of employment.
- •Length of engagement: Long-term contracts with a single client can attract HMRC scrutiny, even if the contract terms favour outside IR35.
Frequently Asked Questions
What is IR35?
IR35 (officially the 'off-payroll working rules') is UK tax legislation designed to combat disguised employment. If HMRC decides your contract resembles employment, you must pay income tax and National Insurance as if you were an employee, even if you work through a limited company.
What are the three main IR35 tests?
The three primary factors HMRC considers are: (1) Substitution — can you send someone else to do the work? (2) Control — does the client control how, when, and where you work? (3) Mutuality of Obligation (MOO) — is there an obligation to offer and accept work? Being outside IR35 on all three is a strong indicator of genuine self-employment.
What does 'inside IR35' mean?
If you are inside IR35, HMRC considers you a 'deemed employee' for tax purposes. You (or your limited company) must pay income tax and National Insurance contributions on the income from that contract, broadly the same as a PAYE employee would pay. You do not receive employee benefits like sick pay or holiday pay.
What does 'outside IR35' mean?
Outside IR35 means HMRC accepts that you are genuinely self-employed for that contract. You can pay yourself through a mixture of salary and dividends, which is typically more tax-efficient than PAYE.
Who decides IR35 status?
Since April 2021, medium and large private sector clients are responsible for determining IR35 status and must issue a Status Determination Statement (SDS). For small private sector clients (fewer than 50 employees, turnover below £10.2m, or balance sheet below £5.1m), the contractor's own company is still responsible for determining status.
Is this IR35 checker accurate?
This tool provides a general indication based on the most important IR35 factors. It is not a substitute for professional advice. IR35 status depends on the full facts of each engagement, and HMRC may weigh factors differently. For a formal determination, use HMRC's CEST tool or consult a qualified IR35 specialist.
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