Code of Practice 8 Investigations

• Key contacts
• Case studies
• FWJ takeaway

A COP8 investigation is a specialist HMRC enquiry used where the department believes a tax loss has arisen from a complex arrangement or avoidance scheme. It is not an allegation of deliberate fraud, but it is a serious investigation that requires careful handling. Early legal advice can help you understand the issues, protect your position and manage your relationship with HMRC throughout the process.

---

At a glance

A COP8 investigation focuses on complex transactions or tax arrangements where HMRC suspects significant tax has been underpaid. These cases often involve detailed information requests and can continue for a prolonged period. We help clients understand the basis of the enquiry, prepare accurate responses and work towards a clear and commercially realistic outcome.

---

What is a COP8 investigation?

COP8 is a form of civil investigation used by HMRC’s Fraud Investigation Service when it believes tax has been lost through the use of complex or bespoke arrangements. It is distinct from a routine enquiry. COP8 does not involve an allegation of deliberate fraud, but HMRC will examine the accuracy of past returns and the structure of the arrangements in detail.

These investigations often involve substantial disclosure of documents, professional advice files and financial records. HMRC’s focus is on understanding the transactions and ensuring the correct amount of tax has been paid.

Summary: COP8 is a serious civil investigation into complex arrangements and requires specialist guidance from the outset.

Why has HMRC opened a COP8 investigation into my tax affairs?

HMRC uses COP8 where it considers a tax advantage may have been claimed incorrectly or where the structure of a transaction appears artificial or unclear. Common examples include certain forms of tax planning, offshore arrangements, share schemes, company reorganisations and bespoke financial structures.

A COP8 investigation does not mean you have done anything wrong. It simply means HMRC wishes to examine the arrangement in detail and confirm whether the correct amount of tax has been paid.

Summary: HMRC opens COP8 investigations when it believes complex arrangements may have caused a tax loss.

How is COP8 different from COP9?

COP8 and COP9 are both specialist investigation procedures, but they are used in different circumstances. COP8 deals with complex arrangements and potential tax loss. COP9 is reserved for cases where HMRC believes deliberate behaviour has occurred. COP9 offers the opportunity to make a full disclosure under the Contractual Disclosure Facility.

If a COP8 investigation suggests that deliberate conduct may have taken place, HMRC may consider escalating the case. This makes it important to manage the enquiry carefully and provide accurate information from the outset.

Summary: COP8 concerns complex arrangements, while COP9 is used where HMRC suspects deliberate behaviour.

What does HMRC expect during a COP8 investigation?

HMRC expects full and timely cooperation. This can include responding to information notices, providing documents, explaining transactions and answering detailed questions about the advice you received when the arrangement was implemented.

The information requested may cover several years. HMRC may also ask for access to correspondence with advisers, company records, agreements and financial statements. Consistency and accuracy are essential to avoid misleading HMRC or prolonging the investigation.

Summary: COP8 investigations involve detailed information requests that must be handled carefully.

What should you do when you receive a COP8 letter?

You should read the letter carefully and seek specialist legal advice immediately. The early stages of the investigation are critical. A clear understanding of the arrangement, the underlying facts and the reasons for the tax treatment claimed is essential before responding.

You should avoid contacting HMRC directly without advice. Any statements you make can shape the direction of the enquiry. You should also gather relevant documents, financial records and any professional advice received when the arrangement was set up.

Summary: The best first step is to take advice and prepare a controlled and accurate strategy for dealing with HMRC.

Can COP8 investigations escalate into more serious action?

COP8 is a civil investigation. However, if HMRC uncovers evidence suggesting deliberate behaviour, the case may be escalated into a COP9 investigation. In serious cases HMRC may consider criminal investigation, although this is unusual.

This is why careful communication, accurate information and a clear understanding of the issues are essential throughout the enquiry.

Summary: COP8 can escalate if HMRC concludes that tax has been deliberately understated.

How long do COP8 investigations take?

There is no fixed timescale. COP8 investigations can last many months or even years, depending on the complexity of the arrangements and the volume of information HMRC requires. Delays can arise if further technical analysis is needed or if HMRC seeks additional documents.

Clients often find the uncertainty difficult, particularly when future tax liabilities are unclear. Clear strategy and regular communication can help manage expectations and bring matters to a conclusion more quickly.

Summary: COP8 investigations can be lengthy and require ongoing engagement.

What are the potential outcomes of a COP8 investigation?

A COP8 investigation may result in HMRC accepting your explanation and closing the enquiry, or it may lead to an adjustment of the tax position. If HMRC considers tax has been underpaid, it may raise assessments, charge interest and impose penalties. Penalties depend on HMRC’s assessment of behaviour and the quality of the disclosure made during the investigation.

In some cases HMRC and the taxpayer may reach a negotiated settlement that resolves the technical issues and avoids prolonged litigation.

Summary: Outcomes can include no change, an amended liability or a negotiated settlement with HMRC.

How can you protect your position during the investigation?

The key is preparation. This includes collecting documents, understanding the advice given at the time of the arrangement and identifying any technical issues that may arise. Clear, accurate and timely responses reduce the risk of escalation or penalty.

You should avoid giving incomplete or speculative answers. HMRC expects openness, but it is essential to ensure that all information provided is correct and consistent with the evidence.

Summary: A careful and documented approach protects both the taxpayer and the business.

How does FWJ help clients facing a COP8 investigation?

We help clients understand the basis of HMRC’s concerns, prepare accurate responses, manage correspondence and engage with HMRC throughout the investigation. We draw on experience across complex tax disputes, COP9 investigations, appeals and tribunal work to guide clients through the process with clarity and confidence.

Summary: FWJ provides experienced support to manage COP8 investigations and achieve a practical and fair outcome.

Simply outstanding service!
From the initial enquiry to the final submission, I have been thoroughly impressed with the advice and communication, depth of knowledge and turnaround time from this firm. Specific thanks must go to Phoebe Pexton for her attention to detail, care and dedication throughout.

A client facing a tax issue

Our expert tax defence team

Our industry leading Tax Disputes team brings decades of experience defending our clients from HMRC investigations and ensuring the best outcomes available to them. The FWJ Tax team includes:

• Andy Lynch. Andy is an expert on a wide range of HMRC claims and before joining FWJ, he spent 18 years at HM Customs & Excise in their National Investigation Service. His experience is unrivalled in all types of HMRC claims including HMRC investigation defence, VAT claims, R&D tax credit defence, Account Freezing Orders, Tax Disclosure, Code of Practice 8 & 9 claims, winding up petition defence and much more.
• Stephen Downie. Stephen is a Partner and a former ACCA accountant who combines financial expertise with deep legal knowledge to deliver clear, commercial advice. He acts for directors, shareholders, insolvency practitioners and private clients in corporate governance disputes, director disqualification defence, and HMRC-related claims including tax avoidance schemes, PLNs, VAT and PAYE security demands. His focus is always on achieving the best outcome for clients as efficiently and cost-effectively as possible.
• Anita Sharma. Anita is a Senior Associate specialising in tax litigation and financial disputes with HMRC. She advises high-net-worth individuals and major commercial clients on appeals against HMRC decisions, complex tax assessments, and enforcement proceedings. Anita has secured interim relief following HMRC revocations to keep clients trading during appeals and is known for achieving practical, results-focused outcomes in high-value disputes.
• Connor Coombs. Connor is a Paralegal in the tax team assisting on a broad range of HMRC investigation and defence matters. He supports clients with Code of Practice 8 and 9 investigations, time-to-pay arrangements, HMRC statutory demands and R&D tax credit disputes. Connor also helps prepare detailed evidence and submissions for use in appeals and settlement negotiations, ensuring cases are presented clearly and effectively.

FWJ did precisely what it set out to do. I am extremely grateful for its assistance.

A client who had received a Request for Security from HMRC for a sum that would have caused their company severe financial difficulties. We helped them to have the entire bill withdrawn