IR35 Checklist for Contractors & Employers
In today’s blog , we revisit IR35 to see where things stand and what contractors and employers (or “clients” if they end up engaging the contractor) need to consider in the contracting world of 2025.
Ensuring IR35 compliance is critical for contractors and employers, and is often the main stumbling block when recruiters and end clients seek to engage a contractor. For several years we have emphasised that, with proper business planning, the issues surrounding IR35 can be successfully navigated. This IR35 checklist offers clear steps for determining status, reviewing contracts, and preparing for HMRC investigations. Use this guide to stay compliant and avoid penalties.
Key Takeaways
- Understanding and determining IR35 status is super important for compliance, with clients now responsible for providing a Status Determination Statement since April 2021.
- Clear communication and documentation among clients, contractors, and recruiters helps prevent misclassification and ensure compliance with IR35 regulations.
- Regular review of contracts and robust documentation of working arrangements will support IR35 status determinations and protect against HMRC investigations.
Understanding IR35 Status Determination
Determining IR35 status lies at the heart of maintaining compliance with the off-payroll working rules. These rules ensure that contractors who operate in a manner broadly equivalent to employees pay similar levels of income tax and National Insurance Contributions. This often applies to contractors working through personal service companies (PSCs) who provide services to an end client, whether in the private or public sector.
Key criteria for assessing IR35 status include the degree of control the client exercises, the contractor’s right of substitution (i.e. whether they can send another suitably qualified individual to carry out the work), and the presence of mutuality of obligation (whether there’s a clear expectation on both sides for work to be offered and accepted). Additional factors, such as the details set out in the written contract, the contractor’s use of their own equipment, and the overall working arrangements, also help determine a contractor’s employment status for tax purposes.
Since April 2021, the responsibility for establishing a contractor’s IR35 status has shifted from the contractor to the end client for medium and large-sized businesses in the private sector, as well as all public sector bodies. Smaller private sector organisations remain exempt from these changes, meaning individual contractors still bear the responsibility for making their own IR35 assessments in those cases. Where the client is responsible, they must issue a Status Determination Statement (SDS) explaining the reasons behind their decision. Many end clients consult with leading experts or use resources like a Qdos status review for support, ensuring they meet their obligations and apply relevant tax rules correctly.
Non-compliance with IR35 can be costly. Contractors deemed ‘inside IR35’ will be liable for income tax, National Insurance Contributions, and potentially pension contributions – aligning their tax profile more closely with that of a direct employee. In some cases, contractors remain compliant by adjusting their arrangements, working through an umbrella company, or seeking independent professional advice. Official guidance, such as HMRC’s online Check Employment Status for Tax (CEST) tool, can also help contractors and clients understand and apply the rules. Ultimately, getting IR35 status right is essential for all parties involved, providing legal clarity, financial stability, and greater confidence in the contracting relationship.
Recent IR35 Legal Developments and Their Impact
The landscape of IR35 continues to evolve through significant legal rulings and HMRC interpretations. Recent developments in 2024-25 have provided greater clarity on key aspects of IR35 determination, particularly regarding Mutuality of Obligation (MoO), control, and substitution rights. These rulings offer important guidance for both contractors and employers in managing their IR35 compliance.
Landmark Court Decisions
The Professional Game Match Officials Ltd (PGMOL) Supreme Court ruling in September 2024 has become a cornerstone case for understanding Mutuality of Obligation. The Court established that MoO exists when there’s a clear obligation for work to be offered and accepted, even in arrangements where engagements are accepted individually. This decision has significant implications for contractors who operate on a project-by-project basis.
In the case of HMRC v S & L Barnes Ltd (August 2024), the Upper Tribunal’s decision highlighted the critical importance of aligning contractual terms with actual working practices. The case of Stuart Barnes, a rugby commentator working through his PSC for Sky TV, demonstrated that written contracts alone cannot determine IR35 status – the reality of the working relationship takes precedence.
Key Responsibilities Under IR35
Under the off-payroll working rules (IR35), the responsibilities for determining and maintaining compliance are shared among clients, recruiters, and contractors. Each party must play its part to ensure transparency, fairness, and adherence to tax regulations.
Clients hold primary accountability. They are required to issue an SDS that clearly outlines the reasoning behind their decision on a contractor’s employment status for tax purposes. If the contractor is deemed “inside IR35,” the client – or the designated fee payer – must deduct the relevant Income Tax and National Insurance Contributions before making payments. Treating these contractors in a manner similar to direct employees reduces the risk of future disputes and ensures tax obligations are properly met.
Recruiters also have an important role. They must securely maintain all IR35-related documentation for the legally specified duration. By initiating discussions about IR35 early in the recruitment process, recruiters set clear expectations and help attract candidates who are comfortable with the determined status. This proactive approach fosters trust, mitigates non-compliance risks, and supports a smoother hiring experience.
Contractors, for their part, should fully understand and agree with the IR35 status assigned to them. Misclassification can lead to legal challenges and substantial financial penalties. Since 6 April 2021, medium and large businesses in the private sector, as well as all public sector bodies, are responsible for determining a contractor’s IR35 status when the contractor provides services through a personal service company. This shift underscores the importance of contractors engaging openly with clients and recruiters to clarify their working arrangements.
Ultimately, clear communication and thorough record-keeping among all parties involved – clients, recruiters, and contractors – are essential. By working collaboratively, they can ensure compliance with IR35, minimise the risk of disputes, and create a stable, transparent environment for everyone.
Reviewing Contracts for Compliance
Regularly reviewing contracts is essential for ensuring IR35 compliance. Engaging an IR35 specialist to assess your agreements helps confirm that both the written terms and the day-to-day working practices align. This step reduces the risk of inadvertently including clauses that suggest an employment relationship, which could result in an ‘inside IR35’ classification.
Avoid using generic, boilerplate contracts. Instead, tailor your agreements to highlight the contractor’s autonomy and control over their own work. For instance, include terms that allow the contractor to decide how and when tasks are completed. Such specific, well-defined clauses can strengthen the case for an ‘outside IR35’ determination.
Documenting Working Arrangements
Thoroughly documenting your working arrangements is a critical step in maintaining IR35 compliance. Accurate and detailed records – such as timesheets, project plans, and communication logs – help demonstrate that the actual working relationship aligns with the terms set out in the contract.
Establishing evidence that supports an ‘outside IR35’ status is especially valuable should inquiries arise. For example, contractors providing their own equipment can emphasise their independence and self-employed status. Similarly, including non-exclusivity clauses in the contract shows that contractors are free to take on multiple clients, further reinforcing their independent standing.
Remember that HMRC will look beyond the written contract. By recording day-to-day activities, client interactions, and consistent use of personal equipment, you create a strong foundation for any future IR35 review.
Educating End Clients and Agencies
Providing end clients and agencies with a clear understanding of IR35 is crucial for preventing blanket ‘inside IR35’ assessments. Misconceptions about obligations, as well as confusion over tools like HMRC’s Check Employment Status for Tax (CEST), can lead to incorrect status determinations, often to the detriment of contractors.
Recruitment agencies play a pivotal role in this process. By facilitating open communication between contractors and clients, they can help ensure that IR35 considerations are well understood. Offering training sessions or informational materials enables clients to distinguish between ‘inside IR35’ and ‘outside IR35’ engagements, improving their decision-making and ultimately reducing the risk of non-compliance.
Bridging the knowledge gap among contractors, agencies, and end clients paves the way for more accurate IR35 determinations. This collaborative approach not only benefits contractors by ensuring fair treatment, but also helps clients navigate their responsibilities more confidently, leading to a smoother, more transparent hiring process.
Securing Confirmation of Arrangements
A Confirmation of Arrangements document plays a crucial role in clarifying the working relationship between the contractor and the end client. By outlining agreed terms and reflecting the reality of day-to-day practices, this document strengthens a contractor’s position should an IR35 investigation arise. It is essential to tailor the Confirmation of Arrangements to accurately represent the unique circumstances of each engagement.
Securing a signed Confirmation of Arrangements may prove challenging within larger organisations, where stakeholders might be cautious about the potential implications. Despite these obstacles, obtaining this confirmation is invaluable. It provides tangible evidence of the contractor’s independence and supports the accuracy of the IR35 status determination, offering greater peace of mind for all parties involved.
Using IR35 Assessment Tools
Let me just preface this section by saying determining employment status for tax purposes under the UK’s IR35 legislation is notably complex, often leading to challenges in accurate assessment. HMRC’s Check Employment Status for Tax (CEST) tool, introduced to assist in this process, has faced significant criticism regarding its reliability and effectiveness. Concerns have been raised about CEST’s exclusion of critical factors such as mutuality of obligation (MOO), a fundamental component in employment status evaluations. Additionally, the tool’s binary question format may not adequately capture the nuances of individual working arrangements, potentially leading to inaccurate determinations. Given these limitations, many contractors and businesses seek independent assessments to ensure compliance with IR35 regulations.
Having said that, tools like the HMRC’s Check Employment Status for Tax (CEST), can help determine whether off-payroll working rules apply to a specific engagement. By providing structured questions and guidance, these tools assist hirers, agencies, and contractors in clarifying the employment status for tax purposes. HMRC will stand by the results generated, provided that all information entered is accurate and up to date (which is the hard part to get right!)
Occasionally, the tool may return an ‘unable to determine’ outcome. In such cases, it offers additional guidance to help users reach a more informed decision. It is advisable to repeat the assessment once the worker’s details are known, as greater accuracy in the information provided can yield a more definitive status result.
To use these tools effectively, gather precise details about the contract, the nature of the services being provided, and the degree of control and independence involved. Retaining printed or electronic copies of both your inputs and the tool’s outcomes creates a valuable audit trail. This documentation can be crucial if questions arise later, helping to demonstrate that all parties have taken reasonable steps towards compliance.
Preparing for HMRC Investigations
Proactive preparation is key when facing HMRC investigations in relation to IR35. Conducting a thorough contract review demonstrates diligence in determining IR35 status and can help mitigate potential penalties. These reviews provide reassurance and strengthen your position in the event of disputes or challenges to status determinations.
Always treat any correspondence from HMRC with urgency and respond promptly. Swift, well-documented communication often helps resolve inquiries more smoothly. Keep all interactions in writing to maintain a clear and traceable record of engagements.
Before meeting with HMRC representatives, consider holding practice sessions to anticipate likely questions and refine your responses. This level of preparedness helps manage expectations and can ultimately lead to more favourable outcomes.
In this regard we recommend you ALWAYS get assistance from an IR35 expert to help with proceedings.
Impact of IR35 on Umbrella Companies
For contractors engaged through umbrella companies, IR35 status concerns are largely removed from the equation. Once a contractor joins an umbrella company, they are treated as an employee of that company, effectively sidestepping the complexities and potential financial risks associated with IR35 compliance.
However, this arrangement means the contractor is effectively classified as ‘inside IR35’. While this simplifies the compliance process and removes uncertainty, it will come at the cost of reduced autonomy and flexibility. Contractors working through umbrella companies may experience less control over their work arrangements compared to those operating as independent PSCs, but the trade-off often lies in securing greater certainty and minimising tax-related risks.
Benefits of Proper IR35 Compliance
Ensuring IR35 compliance brings numerous advantages, including:
- Avoiding Penalties: Correctly determining IR35 status helps prevent costly fines and backdated tax bills.
- Meeting Public Expectations: By paying the appropriate amount of tax, contractors align with societal standards of fairness and responsibility.
- Reducing HMRC Scrutiny: Maintaining compliance lowers the risk of disruptive investigations, preserving contractors’ time and resources.
Complying with IR35 also fosters stronger professional relationships between contractors and clients, building mutual trust and credibility.
Summary
IR35 compliance remains a critical consideration for contractors and employers in 2025. Recent legal developments, particularly the PGMOL and S & L Barnes Ltd cases, have provided clearer guidance on key aspects such as Mutuality of Obligation and the importance of actual working practices over contractual terms.
Success in navigating IR35 requires a thorough understanding of the legislation, proper documentation, and regular reviews of working arrangements. Key actions for maintaining compliance include:
- Ensuring accurate Status Determination Statements
- Maintaining comprehensive documentation of working practices
- Regular review of contracts and arrangements
- Seeking professional guidance when needed
- Preparing thoroughly for potential HMRC investigations
Whether operating through a PSC or considering an umbrella company arrangement, contractors must carefully weigh their options and understand the implications for their working status. Similarly, employers must ensure they meet their obligations regarding status determination and appropriate tax treatment.
The landscape of IR35 continues to evolve through case law and HMRC interpretation. Staying informed about these developments and maintaining robust compliance processes will help both contractors and employers navigate these complex regulations successfully. Remember, while IR35 may seem daunting, with proper planning and professional support, it can be managed effectively.
Frequently Asked Questions
What are the key criteria for determining IR35 status?
The key criteria for determining IR35 status are control (how much say the client has over the work), substitution rights (ability to send someone else to do the work), and mutuality of obligation (whether there’s an ongoing obligation to offer and accept work). Recent court cases, including the 2024 PGMOL ruling, have provided additional clarity on how these factors are interpreted.
Who is responsible for issuing a Status Determination Statement (SDS)?
For engagements with medium and large private sector companies, as well as all public sector bodies, the end client is responsible for issuing a Status Determination Statement (SDS). This statement outlines the IR35 status decision and the rationale behind it. In the case of small private sector clients, the responsibility for determining IR35 status remains with the contractor’s intermediary.
Why is it important to have a comprehensive contract review?
A comprehensive contract review is important to ensure that the written terms align with actual practices, thereby preventing incorrect IR35 determinations. This alignment protects both parties from potential legal and financial repercussions.