IR35 Status Estimator 2026/27 (CEST-style check)

This estimator runs entirely in your browser — enable JavaScript to answer the questions and see your indicative IR35 lean. Nothing you enter is sent to a server. In the meantime, you can use HMRC's CEST tool directly.

This is an estimate to help you understand the factors — NOT an official status determination.

Primary test Could you send a substitute to do the work in your place?
A genuine, unfettered right to send a suitably qualified substitute — that the client cannot unreasonably refuse and that you would pay — is one of the strongest pointers to being outside IR35.
Primary test Who decides how you carry out the work day to day?
Genuine autonomy over how the work is done points outside IR35. A client directing your methods, hours and supervision points inside.
Do you control where and when you work?
Fixed hours at the client's premises under their supervision lean inside; genuine flexibility over location and schedule leans outside.
Primary test Is the client obliged to offer you work, and are you obliged to accept it?
Mutuality of obligation — an ongoing expectation that work will be offered and accepted beyond the current task — is an employment hallmark. A contract for a defined deliverable, with no obligation either way afterwards, points outside.
Do you carry real financial risk on this engagement?
Fixing defects in your own time, quoting fixed prices, buying your own insurance and equipment all show you bear business risk — an outside-IR35 indicator.
Whose equipment do you mainly use?
Providing your own significant equipment points outside; using wholly the client's kit is more employment-like (though common in IT, so weighted lightly).
Are you treated as part of the client's organisation?
A line manager, staff perks, a place on the org chart, managing their employees — all suggest you are 'part and parcel' of the client, leaning inside.
Are you in business on your own account?
Multiple clients, your own marketing, business insurance, a genuine ability to profit from sound management — these show you run a business, pointing outside.

Indicative lean

Borderline — too close to call

0/8 answered

A professional review is strongly advised

Your answers are mixed, or one of the primary tests (substitution, control or mutuality of obligation) points inside. In law a single primary factor can be decisive on its own — a genuine, unfettered right of substitution can settle a case outside IR35 just as a clear failure on control can settle it inside. This estimate cannot weigh those factors the way a tribunal would, so a professional review of your written contract and your actual working practices is the only safe way to establish your status.

Whatever this estimate suggests, confirm your position with HMRC's CEST tool and take professional advice before relying on it.

How IR35 status is actually decided

IR35 — the off-payroll working rules — asks a single question: strip away your limited company, and would the relationship between you and your client look like employment? If it would, the engagement is inside IR35 and broadly the same tax and National Insurance apply as for an employee. If it genuinely wouldn't, you are outside IR35 and trade as a business. The estimator above is a first read on that question; the contractor take-home calculator then shows what each status means for your pay.

Status is not a matter of job title or which box you'd prefer to tick. It is settled by employment case law through three primary tests, supported by a set of secondary factors. No single answer above is a verdict — but the primary tests carry far more weight, and the law allows any one of them to be decisive on its own.

The three primary tests

Right of substitution (personal service). Employees must turn up and do the work themselves. A genuine, unfettered right to send a suitably qualified substitute — one the client cannot unreasonably refuse, and whom you would pay — is one of the strongest pointers to being outside IR35. The catch is that the right must be real: a clause that has never been, and could never realistically be, exercised carries little weight. If the client can veto any substitute or insists on you personally, you are providing personal service, which leans inside.

Control. This is about who decides how, when and where the work is done. A contractor who uses their own methods, sets their own approach and works with little supervision looks like a business supplying a service. Someone told what to do, how to do it, which hours to keep and which priorities to follow — managed like a member of staff — looks like an employee. Day-to-day method is the part that matters most; a client setting an overall deadline or a security policy is normal and not, by itself, employment-like control.

Mutuality of obligation. Employment carries an ongoing, two-way obligation: the employer offers work and the employee is expected to accept it, beyond any single task. A contract for a defined deliverable, where neither side owes the other anything once it's done, points outside. A rolling expectation that you'll keep taking whatever work appears — and that the client will keep finding it for you — points inside.

The secondary factors

When the primary tests are mixed, secondary factors help tip the balance. Financial risk matters: fixing your own defects in your own time, quoting fixed prices, carrying your own professional insurance and standing to make or lose money all mark you out as a business. Equipment is a lighter touch — providing your own significant kit points outside, though using a client's systems is common in IT and weighed gently. Part and parcel looks at whether you've become embedded in the client's organisation: a line manager, staff perks, a slot on the org chart or managing their employees all lean inside. And being in business on your own account — multiple clients, your own marketing and insurance, a real ability to profit from sound management — rounds out the picture of a genuine business rather than a disguised employee.

What the off-payroll rules changed — who determines status

The factors above are long-standing; what changed is who decides and who bears the risk. For engagements with medium and large clients in the private sector, and for all public-sector clients, the client must assess your status and issue a Status Determination Statement, with reasons. If they decide inside, the fee-payer deducts income tax and National Insurance before your company is paid. If your client is small, the old rules persist and the responsibility for assessing status — and the liability — stays with your own limited company. Either way, the estimate here is a personal sense-check, not a substitute for that formal process or for CEST.

Strengthening a genuine outside position

You can present a genuine outside-IR35 engagement honestly — but you cannot contrive one. Make sure the written contract reflects how you really work: a substitution clause is worth nothing if everyone knows it would never be used. Keep control over your own methods and hours where the work allows; avoid drifting into a fixed, supervised, staff-like routine. Contract for defined deliverables rather than open-ended availability. Carry your own insurance, use your own equipment where practical, and keep evidence that you run a real business — other clients, marketing, your own tools. Crucially, get the contract and your working practices reviewed by a specialist, because HMRC and tribunals look past the paperwork to the reality. The methodology behind our take-home figures explains how inside and outside outcomes differ once status is settled.

Frequently asked questions

Does this tool tell me whether I'm inside or outside IR35?

No. It gives an indicative lean based on the well-known employment-status factors so you can see where you stand and what to look at. It is not a status determination. Only the full written contract read alongside your actual working practices settles status, and for medium and large clients the client makes the formal decision in a Status Determination Statement. Always confirm with HMRC's CEST tool and a qualified adviser.

How is this different from HMRC's CEST tool?

CEST is HMRC's own Check Employment Status for Tax service; HMRC says it will stand behind a CEST result provided the answers are accurate and reflect reality. This estimator is an educational warm-up that explains the factors in plain English before you use CEST — it carries no such assurance. Run CEST, and ideally have your contract reviewed, before relying on any answer.

One answer flipped my whole result — is that right?

It can be. The three primary tests — a genuine unfettered right of substitution, control over how you work, and mutuality of obligation — carry more weight than the secondary factors, and in case law a single primary factor can be decisive on its own. That is exactly why the tool flags a professional review whenever a primary test points inside: the maths cannot capture how a tribunal weighs the whole picture.

Who decides my IR35 status under the off-payroll rules?

For engagements with medium and large clients in the private sector (and all public-sector clients), the client decides and issues a Status Determination Statement; the fee-payer deducts tax and National Insurance if you are inside. If your client is small, the responsibility stays with your own limited company. Either way this estimate does not replace that formal process.

Sources & review

Status factors reviewed 12 June 2026 against HMRC's Check Employment Status for Tax (CEST) guidance and established employment-status case law. This page is educational and does not constitute tax, legal or financial advice. By toolseveryday Editorial Team — Researching and verifying UK contractor tax figures against HMRC guidance.