UK IR35 Status Determination 2026/27: CEST, Case Law, Tests

Q How do I check my IR35 status in 2026/27?

IR35 status turns on mutuality of obligation, control, and personal service. Since April 2021 medium and large clients make the determination via a Status Determination Statement; small clients leave it to the contractor's company. HMRC's CEST tool gives an indicative result.

Q What is IR35 / off-payroll working in 2026/27?

IR35: anti-avoidance legislation taxing personal service company (PSC) contractors as employees when relationship resembles employment. Statutory basis: ITEPA 2003 Chapter 8 (intermediaries) + Chapter 10 (off-payroll working since 2017/2021). Two regimes: Chapter 8 = applies where engagement is between PSC + small client. PSC determines own status + pays applicable tax/NI. Chapter 10 = applies where engagement is between PSC + large/public sector client. CLIENT determines status + may apply PAYE/NI deductions. Public sector reform 2017: large public-sector clients started determining IR35 status. Private sector reform April 2021: extended to large private-sector clients. Finance Act 2020 Schedule 1. Why IR35 exists: prevents employees disguising as PSC contractors to avoid Employee + Employer NI + PAYE. Effect when inside IR35: deemed payment (Chapter 8) or Chapter 10 PAYE deductions. Net result: equivalent to employee tax + NI on relevant earnings. Effect when outside IR35: PSC operates as normal limited company. Salary + dividend extraction at preferred tax rates.

Q Who determines IR35 status - small vs large client rules?

Determined by CLIENT SIZE. Small client: under section 60A Income Tax (Earnings and Pensions) Act 2003, a company is small for a tax year if the small companies regime applied to it for its last financial year whose accounts filing deadline fell before that tax year began (or if it is too new to have such a year). That regime uses the Companies Act 2006 section 382 test: meeting two or more of turnover not more than £10,200,000, balance sheet total not more than £5,100,000, and not more than 50 employees (separate rules cover joint ventures, subsidiaries, LLPs and other undertakings, and other persons in ss.60B-60G), with a change of size counting only once it has held for two consecutive financial years (s.382(2)). Those are the figures for financial years beginning before 6 April 2025; for financial years beginning on or after that date they rise to £15,000,000 turnover and £7,500,000 balance sheet (SI 2024/1303). For 2026/27 engagements: a client with a usual 12-month financial year is sized on a financial year that began before 6 April 2025, so the £10,200,000 / £5,100,000 figures apply; HMRC says the earliest tax year the higher figures can affect is 2027/28 (ESM10006A). Large client: does not qualify as small. Public sector clients: always treated as "large" regardless of size. Determination responsibility: Small client engagement: PSC self-determines status via Chapter 8 ITEPA 2003. PSC operates Chapter 8 deemed payment calc if inside IR35. Large client engagement: client must determine status via Status Determination Statement (SDS). Who is liable: the fee-payer (the person in the chain immediately above the worker's intermediary, often an agency) is treated as making the deemed payment and operates PAYE and NI on it (ITEPA s.61N(2)-(3)). The client takes that liability instead until it gives an SDS (s.61N(5)), and a statement made without reasonable care is not an SDS (s.61NA(2)); it also takes it if it misses the 45-day disagreement deadline (s.61T(3)). Where the fee-payer is not a qualifying person, liability can move up the chain (s.61N(5A)-(7)). Penalties: Schedule 24 FA 2007 penalties attach to careless or deliberate inaccuracies in documents given to HMRC, such as returns, not to the SDS itself. Status Determination Statement (SDS): states the client's conclusion (inside or outside) and explains the reasons for it; it is not a valid SDS if the client failed to take reasonable care (ITEPA s.61NA). Provided to PSC + next entity in supply chain. Disagreement: the worker or deemed employer can tell the client the SDS conclusion is wrong. The client must either confirm it with reasons or issue a new SDS; if it has not done so within 45 days beginning with the date it received the representations, the client takes on the fee-payer's PAYE liability from the end of that period until it does (ITEPA s.61T(3)). Practical note: many contractors found small-client engagements ambiguous - check client's published accounts on Companies House to verify size.

Q What is the HMRC CEST tool + its limitations?

CEST (Check Employment Status for Tax): HMRC's free online tool for determining IR35 status. gov.uk/guidance/check-employment-status-for-tax. Process: client/PSC answers ~15-25 yes/no questions about engagement. Tool produces binding determination (HMRC commits to standing by output IF answers honest). Strengths: free, fast (15 mins), HMRC-backed, can be used as audit trail. Limitations: (a) Heavily simplified - real-world employment status involves dozens of factors not in CEST. (b) Over-classifies inside IR35 - industry analysis suggests 60%+ of CEST outputs come back inside IR35 even where strong outside-IR35 indicators exist. (c) MOO test absent: CEST infamously doesn't ask Mutuality of Obligation questions despite this being a fundamental test in case law (Ready Mixed Concrete). HMRC argues MOO is implicit but tribunals consistently disagreed. (d) Borderline outputs unclear: CEST may say "unable to determine" - leaving parties without certainty. (e) Updates lag case law: PGMOL [2024] UKSC + Atholl House [2023] UKUT case law not fully reflected. Alternative tools: QDOS commercial status review service (~£100-£250 per assessment) - more nuanced. IPSE Confidence assessment tool. Brookson, Markel, Bauer + Cottrell specialist IR35 reviews £300-£1,500. Best practice: use CEST as starting point + specialist confirmation for important engagements + retain audit trail of all status determinations.

Q What are the 5 key IR35 case-law tests?

UK courts established multi-factor tests over decades. No single test conclusive - balance of factors. (1) Mutuality of Obligation (MOO): Ready Mixed Concrete v MPNI [1968]. Does client have obligation to offer work + contractor obligation to accept? Employee = yes; self-employed = no obligation either side. (2) Personal service and substitution: the first Ready Mixed Concrete condition is that the worker must provide their own work and skill (ESM0531). In Express & Echo v Tanton [1999] IRLR 367 an obligation to arrange and pay for a substitute was wholly inconsistent with a contract of service (ESM0532); in Usetech v Young (76 TC 811) a weaker clause pointed to personal service (ESM0533). HMRC: "It is the right to provide a substitute that is important, not whether that right is exercised" (ESM0530). In Atholl House the Court of Appeal said the Autoclenz approach cannot apply to the IR35 hypothetical contract (ESM7335). (3) Control: Ready Mixed Concrete v MPNI [1968] 2 QB 497, which HMRC says reaffirmed control as an essential and necessary consideration (ESM0516). Who decides how / when / where work done? Client direction = employee-like. Contractor independence = self-employed. Synaptek Ltd v Young (75 TC 51) is an IR35 case applying these tests to an IT consultant's service company (ESM7260). (4) Financial Risk + Provision of Equipment: Market Investigations v Minister of Social Security [1969] 2 QB 173: the fundamental test is whether the person is in business on their own account, and relevant factors include own equipment, hiring helpers, financial risk, investment and management, and opportunity to profit from sound management (ESM7040). Does contractor bear business risk? Own laptop / software / professional indemnity insurance / bad debt exposure = self-employed indicators. (5) Overall picture: Hall v Lorimer (Court of Appeal, 66 TC 349), a freelance vision mixer held self-employed. The court said the exercise is not a checklist: paint a picture from the accumulation of detail and evaluate the overall effect (ESM7160). Recent case law: HMRC v PGMOL [2024] UKSC 29 (part-time football referees): the Supreme Court took Ready Mixed Concrete as the starting point, held that the minimum requirements of mutuality of obligation and control were met for the individual match contracts, and remitted the case to the First-tier Tribunal to decide status on all the circumstances (press summary). HMRC v Atholl House Productions (Kaye Adams, BBC): the Court of Appeal held that Ready Mixed Concrete and Hall v Lorimer are not two different tests, set aside the Upper Tribunal decision and remitted the case to the First-tier Tribunal (ESM7335). Industry sector matters: courts increasingly consider sector norms (IT contracting, journalism, broadcasting). Multi-factor balance: courts don't weight equally - weight depends on case facts. No formulaic test exists.

Q What is the Status Determination Statement (SDS) format?

SDS: written statement from large/public-sector client to PSC explaining IR35 determination + reasons. Statutory basis: Section 61NA ITEPA 2003. Mandatory elements: (1) conclusion (inside IR35 / outside IR35); (2) the reasons for that conclusion. A statement is not a valid SDS if the client fails to take reasonable care in reaching its conclusion (Section 61NA(2)). Provided to: (a) PSC / contractor directly; (b) next entity in supply chain (agency or end-client). Both must receive SDS. Timing: BEFORE work commences, ideally before contract signed. Until the client gives an SDS, the client itself is treated as the fee-payer and is liable for the PAYE and NI (ITEPA s.61N(5)); a statement made without reasonable care does not count (s.61NA(2)). Status disagreement process: the worker or deemed employer can make representations that the SDS conclusion is incorrect at any time before the final chain payment (ITEPA s.61T(1)); the statute sets no shorter window. The client must either (a) give a statement that it has considered the representations, decided the conclusion is correct, and why, or (b) issue a new SDS with a different conclusion, the date from which it applies, and withdrawal of the old one (s.61T(2)). If the client has not done either within 45 days beginning with the date it received the representations, it is treated as the fee-payer for PAYE from the end of that period until it complies (s.61T(3)). Worker rights post-disagreement: if client confirms inside-IR35 determination despite worker disagreement, worker can: (a) accept Chapter 10 PAYE deductions; (b) decline engagement; (c) pursue tribunal claim for employee rights if PSC engagement appears to be disguised employment with substantive employee benefits. Common SDS pitfalls: cookie-cutter "blanket" determinations (HMRC dislikes - requires case-by-case); CEST-only reasoning without supporting analysis; failure to re-issue SDS when engagement changes.

Q Inside IR35 tax treatment - Chapter 10 mechanics?

Chapter 10 ITEPA 2003 + Off-Payroll Working Rules: where large client determines PSC engagement inside IR35, the fee-payer (typically the agency, or the client if there is none) is the deemed employer. It may deduct the worker's Income Tax and employee NI from the payment before paying the PSC (ITEPA s.61S, ESM10021). Employer NI is the deemed employer's own cost and is not deducted from the deemed payment; if the contract rate is cut to pass PAYE or NI costs back to the PSC, the deemed payment is worked out as if they had not been passed on (s.61Q(4)). Any commercial effect on the rate is a contract matter. Worked example - £600 day rate inside IR35, 2026/27, England: 220 days = £132,000 deemed payment (no VAT, materials or expenses). Personal Allowance at that income: £0. Income Tax £45,603; employee NI £4,651. Paid to the PSC: £81,746. Separately, the deemed employer pays employer NI of £19,050 (15% above £5,000). Figures computed from the 2026/27 ruleset on a single annual deemed payment; real payroll runs period by period.

Q Outside IR35 confirmation - what evidence supports?

Strong outside-IR35 evidence portfolio: (1) Right of substitution clause: contract gives a GENUINE right to send a substitute whom the PSC pays, without an unlimited client veto. HMRC says it is the right that matters, not whether it is exercised (ESM0530). (2) No mutuality of obligation: contract states neither party has obligation to offer / accept future work. Engagement is project-based not ongoing. (3) Control evidence: contractor sets methods, work location flexible, working hours negotiable. Use own tools/laptop. (4) Financial risk: PSC has professional indemnity insurance £1m+, public liability insurance, bears bad debt risk, invests in own equipment + training. (5) Business setup: PSC operates as genuine business - website, business cards, multiple clients (or actively marketing for them), separate business bank account, accountancy retained, business plan, marketing activity. (6) Integration evidence: NOT in client's org chart, NOT receiving employee benefits, separate company email, attends external industry events. (7) Sector norms: engagement matches typical contracting patterns in the sector. (8) Multiple clients: worked for 2+ unrelated clients in the year (or genuinely seeking). (9) Contract terms align with practice: contract reflects reality of working relationship - not "paper exercise". (10) Annual status review: regular re-assessment of engagement vs status. Documentation: maintain contracts, SDS responses, sales activity, accountancy correspondence, insurance certificates. IPSE membership + IR35 insurance: some contractors buy insurance against the cost of an HMRC status challenge.

Q PGMOL Supreme Court decision 2024 - what changed?

HMRC v Professional Game Match Officials Ltd (PGMOL) [2024] UKSC 29: Supreme Court ruled on football match official status. Major IR35 case law clarification. Background: PGMOL (referees' association) treated referees as self-employed. HMRC argued employee status. Multiple tribunal + appellate hearings 2017-2024. Supreme Court ruling: (1) MOO (Mutuality of Obligation) confirmed as central test. Court rejected HMRC argument that MOO is implicit in any work-for-payment arrangement. Specific MOO must be tested. (2) Multi-factor analysis required: no single factor determinative. Tribunal must weigh all factors based on case facts. (3) Sector norms relevant: refereeing's unique structure (volunteer matches + paid matches; minimal control during 90 minutes of match; etc.) considered. (4) HMRC's narrow interpretation rejected: Supreme Court rejected HMRC's attempt to broaden employee status via deeming. Practical implications: For HMRC: must use multi-factor analysis in IR35 investigations + acknowledge MOO importance. Status determinations more nuanced. For PSCs: stronger basis to challenge inside-IR35 SDS where MOO is genuinely absent + multi-factor balance favours self-employment. For clients (Chapter 10): SDS reasoning must address MOO explicitly. Cookie-cutter "blanket inside" determinations more vulnerable to challenge. CEST tool implications: HMRC has not yet updated CEST to fully reflect PGMOL. Industry pressure for tool revision. Going forward: 2025-2026 will see lower-court application of PGMOL principles. Multiple cases pending First-tier Tribunal that may significantly shift IR35 landscape.

Q PSC, umbrella or direct employment: which should a contractor use?

Three main contractor arrangement options post-2021 reform: PSC (Personal Service Company): contractor's own limited company. Best for outside-IR35 work + high income (£50k+ profit). Tax-efficient salary + dividend. Director responsibilities (Companies House, CT600, etc.) + £1,500-£3,000/yr accountancy. Umbrella Company: employed by umbrella, deducts PAYE + NI on contract rate, pays you net. Common post-2021 for inside-IR35 contracts. Simple admin, no Companies House obligations. Some retain salary sacrifice for pension. Margin cost: typically £15-£30/week or 1-3% of contract value. Direct employment: PAYE employee of end-client. Stable, full employee rights (holiday, sick, pension AE). Less flexibility / lower day-rate vs contract equivalent. Decision factors: If consistently outside IR35: PSC. Maximum tax efficiency. If consistently inside IR35: umbrella for simplicity OR PSC if you have outside-IR35 work elsewhere or want to maintain incorporated business identity. If hybrid contractor career: PSC + umbrella interchange depending on contract. Common approach. If career stability sought: direct employment. Less upside but lower stress. Switching cost: closing PSC via MVL (Members' Voluntary Liquidation) gets Business Asset Disposal Relief (BADR) 18% on retained profits. See LTD MVL closure guide. Important - umbrella diligence: some umbrellas have poor compliance track records. Check FCSA / Professional Passport accreditation. Avoid umbrellas offering "tax advantageous" structures - usually HMRC-prosecutable mini-umbrellas / mini-UVATs / disguised remuneration schemes.

Q What is mini-umbrella / disguised remuneration risk?

Mini umbrella company fraud: HMRC describes organised crime groups breaking one umbrella company into many small limited companies, each employing a few workers, so they can claim small-business incentives such as the Employment Allowance or the VAT Flat Rate Scheme, or build up tax debts and close without paying. Workers may be moved between them without being told, and can have their tax and NI stolen. On 17 July 2025 the Upper Tribunal ruled the model in Elphysic Limited and others v HMRC fraudulent (HMRC: Mini umbrella company fraud). Moved between umbrellas: HMRC's Spotlight 71 (13 June 2025) warns agency workers and contractors who are moved between umbrella companies, which it says can be used to hide tax avoidance (Spotlight 71). Disguised remuneration schemes: variants involving loans, employee benefit trusts, contractor loans, profit-share structures. 2019 Loan Charge: a charge on disguised remuneration loans outstanding on 5 April 2019. After the 2019 independent review it applies only to loans made on or after 9 December 2010 (up to 5 April 2019 for loans received while employed, 5 April 2017 while self-employed), with a further exclusion for unprotected years where the scheme use was reasonably disclosed (GOV.UK). Indicators of risky scheme: take-home pay that looks too good to be true; being moved to a new umbrella company at short notice, or paid by a different company from the one you contracted with (Spotlight 71); convoluted multi-company structures; "we'll handle the tax" promises; pressure to sign before reading terms; offshore elements (Isle of Man, Cayman, etc.); claims of HMRC approval (HMRC says it does not approve or endorse umbrella companies or tax avoidance schemes). Penalties for use: full tax restitution + Schedule 24 FA 2007 inaccuracy penalties on careless or deliberate errors in returns: for domestic (category 1) inaccuracies up to 30% (careless), 70% (deliberate) or 100% (deliberate and concealed) of the potential lost revenue, higher for offshore categories 2 and 3 (para 4), reducible for disclosure (para 10) + potential criminal prosecution, including for the common-law offence of cheating the public revenue, which the Theft Act 1968 s.32(1)(a) preserved in England and Wales (the section's extent) plus HMRC enforcement under Schedule 36 FA 2008 information powers. If currently in scheme: see COP9 / CDF guide + specialist tax solicitor immediately. Voluntary disclosure dramatically better than HMRC discovery.