No contract is IR35 compliant, and a template sold as one is selling the wrong product. The rules ask what the engagement would be if the intermediary were removed, and that question is answered by what actually happens: who directs the work, whether anyone else could do it, and whether either side is obliged to offer or accept more of it. A contract matters because it is the first evidence of those things and because a clause that contradicts reality is worse than no clause at all, having put the contradiction in writing.
The three ingredients a contract can speak to
CONTROL: who decides how, when and where the work is done. A clause saying you control the manner of the work is meaningful only if you do. SUBSTITUTION: a genuine right to send someone else, exercisable in practice rather than on paper. A right hedged with client veto over any substitute is not a right. MUTUALITY OF OBLIGATION: whether the client must offer work and you must accept it. A contract for a defined deliverable with no obligation to offer more is the shape that helps; a rolling arrangement with no stated end is the shape that does not.
Why the practices win
Tribunals and HMRC look through the written terms to the reality, and the reality is what you can show with emails, timesheets, project documents and the way the client's own people talk about you. If the contract says substitution and nobody has ever been offered one, the clause carries little weight. If the contract says you control the work and you attend the client's daily stand-up, take tasks from its manager and work its hours, the clause carries none. The useful order is to arrange the work properly and then write it down, not the reverse.
What an outside IR35 template is actually good for
A starting point and a checklist, and that is a real use. A well-drafted contractor agreement will at least not contain the clauses that sink an engagement: notice periods that read as employment, entitlement to client holiday or sick pay, a job title, line management, an obligation to work fixed hours on site, or a clause requiring you personally and only you. Reading a template to find what is missing from your own contract is worthwhile. Signing one and believing the engagement is now outside is not.
Where the IR35 risk actually sits now
For medium and large clients the client makes the determination and the fee-payer carries the tax, so the contractor's exposure on a current engagement is smaller than it was and the argument to be had is with the client rather than with HMRC. Where the client is small, the original rules apply and your own company is responsible, which is the case where a well-evidenced contract and a documented review earn their money. Historic engagements under the old rules stay with your company either way, which is why keeping the paperwork from closed contracts is not paranoia.
How to work outside IR35 in practice
Take defined pieces of work with a stated outcome rather than open-ended time. Use your own equipment where you reasonably can. Keep other clients, or at least the freedom to take them. Do not accept line management, an employee job title, a company email signature that presents you as staff, or an obligation to be available. Invoice for the deliverable. Ask for the Status Determination Statement before you start and read its reasons, and if they are wrong, make representations: the client must respond within 45 days.
Questions people ask about ir35 compliant contract
Is there such a thing as an IR35 compliant contract?
No. There are contracts that match the work and contracts that do not. The rules test the engagement, and the working practices override the written terms wherever the two disagree.
Does a right of substitution put me outside IR35?
Only if it is genuine and exercisable. An unfettered right that has never been tested is weaker evidence than one that has been used, and a right the client can veto for any reason is not a right.
Will an outside IR35 contract template help?
As a checklist, yes: it shows the clauses that should not be there. As protection, no. A clause that contradicts how the work is actually done is evidence against you rather than for you.
Who carries the risk if the determination is wrong?
With a medium or large client, the fee-payer, normally the agency. With a small client, your own company. Historic engagements under the original rules stay with your company whatever the client's size.