ExternalOS

A fast, honest IR35 check.

Modelled on the seven factors that UK tribunals actually turn on when testing contractor status.

HMRC's own CEST tool is long, awkward, and famously gives "undetermined" around one in five times. This is a simplified version, built around the same seven factors UK case law actually turns on.

Your verdict is purely educational. If the stakes are high, follow it up with a proper status review.

SubstitutionCan you genuinely send someone else to do the work?
ControlWho decides what, how, when and where the work is done?
Mutuality of obligationIs the ongoing work relationship baked in?
Financial riskWhat do you actually lose if it goes wrong?
EquipmentWhose kit, tools and licences are in play?
IntegrationHow embedded are you in the client's org?
ExclusivityDo you have, or could you have, other clients?

Answer honestly.

Think about how the work really happens, not just what the contract says. Tribunals look at both.

Question 1 of 7 14%
03 / Your verdict

The result.

Based on the weighting HMRC and UK tribunals apply to each factor.

Verdict

Why we reached this verdict

    Your next steps

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      Not legal advice

      This checker is a simplified educational tool. It's modelled on the case-law factors HMRC and UK tribunals use when testing IR35 status, but it does not replace HMRC's CEST tool, an accountant, or legal counsel. Status disputes turn on the full picture of a working relationship, including written contract terms and the day-to-day reality of how work actually gets done. If the stakes are high, get proper advice before acting on a result.