Know your status before the client decides it for you — and keep the most of an inside-IR35 rate when it happens.
- £39
- 8 modules
- Updated at every Budget
- 30-day refund
A status determination is not a formality. For medium and large clients the client decides whether you are inside or outside IR35 and must give you a Status Determination Statement; for small clients you still decide yourself. Most contractors cannot say which type of client they are working for, which means they cannot say who is making the decision about their tax.
The rate maths is where the money moves. The same £600 a day looks completely different through an umbrella, through agency PAYE, or as a deemed payment through your own company, and the umbrella market itself changed in April 2026. This guide sits on both sides of the line: how to evidence an outside position properly, and how to keep the most of an inside one when that is what you are handed.
What’s inside
- Who decides: the small-client test, the Status Determination Statement, and the client-led disagreement process
- Substitution, control and mutuality — contract wording that helps, wording that destroys the position, and why practices must match
- CEST walked through including where it is weakest and how to keep evidence of the run
- Living outside IR35: working practices, a confirmation of arrangements letter, and the insurance an independent contractor carries
- The inside maths at 2026/27 rates: umbrella, agency PAYE and a deemed payment compared at £400, £600 and £800 a day
- Umbrella companies after April 2026 — what changed, how to sanity-check one, and a payslip audit line by line
- Converting an outside rate to an inside rate with the formula, plus a contract red-flag checklist
- A mixed portfolio, and whether the limited company still earns its keep
The templates
An outside-to-inside rate converter, a status evidence file index, an umbrella payslip checker, and the contract red-flag checklist.
Where to start
Start with the small-client test and the evidence file: what your contract says, what actually happens on the ground, and whether the two match. Run CEST and keep the output, then use the converter to see what an inside rate needs to be to leave you where you are today. The payslip checker is for the month after you join an umbrella, when the first payslip arrives and nothing on it adds up.
Buying more than one? All ten 2026/27 courses, 262 pages and 44 templates, are £119 against £328 at full price. See the full course list.
Not for you if: you work in the public sector under a different engagement model, or your contract is governed outside England and Wales.
Questions people ask before buying
I am a sole trader, not a limited company. Does IR35 apply?
IR35 applies to work done through an intermediary, usually your own limited company. Sole traders face the ordinary employment-status test instead, which the guide also covers, because clients often confuse the two.
Does it cover the April 2026 umbrella changes?
Yes. The umbrella module explains what changed, how to sanity-check an umbrella before you sign, and how to audit a payslip line by line.
Will this tell me whether my contract is inside or outside?
It gives you the tests, the CEST walkthrough and the evidence to build, so you can reach a defensible view and challenge a determination you disagree with. It is not a legal opinion on your specific contract.
Is the rate converter a spreadsheet?
Yes, an Excel sheet with the 2026/27 rates built in. Change the day rate, the expenses or the umbrella margin and it recalculates.
General information, not tax or legal advice. Figures checked against HMRC and other primary sources at publication — see our editorial policy.