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Free tool · Rules for 2025/26

Am I inside or outside IR35?

If you work through your own limited company, answer seven questions for an indicative view of whether IR35 applies to a contract, and find out who decides.

Who is your client?

A private sector client is small if it meets two or more of the Companies Act small company tests: turnover, balance sheet total, and 50 employees or fewer. The turnover and balance sheet limits rose to £15 million and £7.5 million for financial years starting on or after 6 April 2025.

1. Substitution. Could you send someone else to do the work instead of you?

A genuine right to send a substitute, who you'd pay, is one of the strongest signs of being outside IR35.

2. Control: how. Who decides how the work is done?

Think about methods and techniques, not the result the client wants.

3. Control: when and where. Who decides your working hours and where you work?

Working on the client's site because that's where the systems are is not the same as being told to.

4. Control: what. Can the client move you onto other work outside the agreed project?

Being moved between tasks like a member of staff points towards employment.

5. Mutuality of obligation. Does the client have to offer you more work, and do you have to accept it?

Ongoing obligations on both sides are a feature of employment.

6. Financial risk. Could you lose money on this work?

For example a fixed price, fixing mistakes in your own time and at your own cost, or significant costs you can't recharge.

7. Part and parcel. Are you treated like one of the client's staff?

Managing their staff, a staff email signature, staff benefits, parties or training.

Answer all 7 questions to see an indicative result (0 of 7 done).

How IR35 works

IR35, the off-payroll working rules, applies when you'd be an employee of your client if you worked for them directly. If it applies, tax and National Insurance are due on your fees as if they were a salary.

Who decides depends on the client. Since April 2021, medium and large private and voluntary sector clients decide and must give you a Status Determination Statement, as public sector bodies have since April 2017. If your client is small, your own company decides.

The main tests are substitution (whether you could send someone else), control (over how, when, where and what you work on), mutuality of obligation, financial risk, and whether you're part and parcel of the client's organisation. No single test decides it: the whole picture, in the contract and in practice, does.

This check is indicative only. It is not a status determination, and HMRC won't rely on it. Use HMRC's Check Employment Status for Tax tool for a view HMRC will stand by.

General information, not tax advice. See Check employment status for tax and Understanding off-payroll working (IR35) on GOV.UK.