IR35 Case Law: Key Tribunal Decisions

IR35 legislation is shaped not just by statute but by the case law that emerges from tax tribunal decisions. Each case refines how the employment status tests are applied, clarifying what constitutes genuine self-employment and what amounts to disguised employment. For contractors, understanding the key cases provides practical insight into how HMRC and the courts assess working arrangements.

In this guide, I review the most significant IR35 tribunal decisions and extract the lessons that matter for contractors in 2026.

The Foundation: Ready Mixed Concrete (1968)

While this case predates IR35 by over 30 years, it remains the bedrock of employment status law in the UK. In Ready Mixed Concrete (South East) Ltd v Minister of Pensions and National Insurance, the court established the three-part test for employment:

1. The worker agrees to provide their own work and skill in exchange for payment (personal service).
2. The worker agrees that the employer will have a sufficient degree of control (control).
3. The other terms of the contract are consistent with employment (mutuality of obligation and other factors).

This test continues to be cited in virtually every IR35 case. For contractors, the key takeaway is that all three elements must be present for employment to exist. If any one is absent — particularly personal service (substitution) or control — the relationship may not be employment.

According to HMRC's Employment Status Manual, the Ready Mixed Concrete test provides the framework for all subsequent employment status analysis.

Autoclenz v Belcher (2011)

This Supreme Court case established a critical principle: courts should look at the reality of the working relationship, not just the words in the contract. In Autoclenz Ltd v Belcher, car valets were engaged under contracts that described them as self-employed, with substitution rights and no mutuality of obligation. In reality, they were required to attend personally, could not substitute, and were given regular work.

The Supreme Court held that the written terms did not reflect the true agreement between the parties, and the valets were employees.

Lesson for contractors: Your contract must reflect reality. Having a substitution clause on paper is worthless if you have never substituted and the client would never accept it. HMRC and the tribunals will look at what actually happens, not what the contract says.

Dragonfly Consulting v HMRC (2008)

In this case, an IT consultant working through her personal service company was found to be outside IR35. The key factors were:

• She had a genuine right of substitution and had actually used it
• She bore real financial risk (providing her own equipment and insurance)
• She had significant control over how and when she worked
• She was not integrated into the client's organisation

Lesson for contractors: This case demonstrates the value of exercising your substitution right. The fact that the consultant had actually sent a substitute — not just had the contractual right to do so — was a powerful factor in the tribunal's decision.

Atholl House Productions v HMRC (2019-2022)

The Atholl House case involved a BBC presenter, Kaye Adams, and became one of the most closely watched IR35 cases in recent years. The case went through multiple tribunal hearings and appeals, with different levels of the tribunal reaching different conclusions.

The First-tier Tribunal found Adams was outside IR35, but HMRC appealed. The Upper Tribunal allowed the appeal and remitted the case, finding errors in the original tribunal's approach to the control test. The case was reconsidered, and the outcome highlighted the difficulty of applying IR35 to media engagements.

Lesson for contractors: Even experienced tribunals can disagree on IR35 status, demonstrating how inherently difficult these determinations are. The case also emphasised that control must be assessed realistically — having theoretical freedom to work elsewhere does not negate the practical control a client exercises during the engagement.

MDCM Ltd v HMRC (2019)

This case involved an IT contractor who was found to be inside IR35. The tribunal focused on the lack of a genuine right of substitution and the high degree of client control over the contractor's work. The contractor worked exclusively for one client, attended daily stand-up meetings, and had no real ability to send someone else in his place.

Lesson for contractors: Working exclusively for one client, attending regular team meetings, and lacking substitution rights are strong indicators of employment. If your engagement has these characteristics, your IR35 position is weak.

Kickabout Productions v HMRC (2022)

Involving ITV presenter Lorraine Kelly, this case was decided in the taxpayer's favour. The tribunal found that Kelly's unique personal qualities were central to the engagement and that she had significant creative control. The relationship was genuinely one of client and independent contractor.

Lesson for contractors: The personal brand and unique attributes of the worker can be relevant. If you bring specialist expertise that is uniquely yours — rather than filling a generic role — this supports an outside IR35 determination. However, this factor is more relevant to creative and media professionals than to contractors in technical roles.

Christa Ackroyd Media Ltd v HMRC (2018)

Another BBC presenter case, this time involving the Look North presenter Christa Ackroyd. The tribunal found her inside IR35. The key factors were the BBC's significant control over her work, the requirement for personal service (no substitution), and the mutuality of obligation inherent in her engagement.

Lesson for contractors: The tribunal distinguished this case from Lorraine Kelly's by noting that Ackroyd had less creative freedom and more client control. The comparison illustrates that seemingly similar engagements can have different outcomes depending on the specific facts.

What the Case Law Tells Us

Looking across the body of IR35 case law, several themes emerge:

Reality trumps contracts. The tribunals consistently look beyond the written contract to assess what actually happens in practice. Contract terms are the starting point, but they are not determinative.

Substitution is powerful. A genuine, exercised right of substitution is one of the strongest indicators of self-employment. But it must be real — a paper right that has never been and could never be exercised is valueless.

Control is multifaceted. The tribunals assess control over what is done, how it is done, when it is done, and where it is done. No single element of control is decisive; it is the overall degree of control that matters.

Integration matters. Being treated as part of the client's organisation — attending meetings, having a company email, being on the org chart — pushes towards employment.

Financial risk supports self-employment. Contractors who invest their own money, could make a loss, and bear the cost of correcting defective work are more likely to be outside IR35.

Each case turns on its facts. The tribunals repeatedly emphasise that each engagement must be assessed individually. Precedent provides guidance but does not dictate outcomes.

For a practical guide to applying these lessons, see my article on how to determine your IR35 status. And for guidance on structuring your contracts to reflect genuine self-employment, read my guide on IR35-compliant contracts.

Staying Current

IR35 case law continues to develop. New tribunal decisions refine the tests and clarify grey areas. As a contractor, staying informed about key decisions helps you assess your own position and respond to changes in how the law is interpreted.

As IPSE regularly reports, the volume of IR35 cases reaching the tribunals has increased since the off-payroll reforms, providing an ever-richer body of guidance for contractors and their advisers.

For help managing the financial aspects of your contracting career, Accounted handles bookkeeping, tax deductions, and self-assessment filing. I will keep your finances in order so you can focus on your work. Visit our features page to learn more.

Penny, your AI bookkeeper, tracks your tax position in real time and flags opportunities to reduce your bill. Meet Penny →