Background to COP8 and COP9
HMRC uses Codes of Practice 8 and 9 (COP8 & COP9) to investigate potential tax underpayments and suspected evasion:
- COP8 investigates cases of suspected mistakes or underpayments, typically where there is no evidence of deliberate concealment.
- COP9 is applied when HMRC suspects deliberate tax evasion, often including potential criminal investigation.
Most taxpayers will never encounter COP8 or COP9 — but if you do, it’s critical to seek specialist advice immediately.
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Initial Letter From HMRC
When HMRC initiates a COP8 or COP9 investigation, the opening correspondence usually includes:
- Notification that your tax affairs are under review.
- A copy of Code of Practice 8 or 9, depending on the case.
For COP9 cases, the letter may also indicate that HMRC is considering criminal investigation unless a full disclosure is made.
What HMRC Expects
If contacted under COP8 or COP9, HMRC will generally expect you to:
- Disclose all relevant income or tax errors
- COP8: Correct mistakes and underpayments.
- COP9: Full disclosure of deliberate underpayments to potentially avoid prosecution.
- Respond within the specified timeframe
HMRC often provides a limited window to submit an outline disclosure.
Failing to respond may lead to full civil or criminal investigation.
| Feature | COP8 | COP9 |
|---|---|---|
|
Focus |
Civil investigation, unintentional errors |
Suspected deliberate tax evasion or concealment |
|
Severity |
Moderate penalties |
Severe penalties; potential criminal prosecution |
|
Triggers |
Mistakes, late returns, discrepancies |
Deliberate concealment, offshore income, complex schemes |
|
Voluntary Disclosure |
Can reduce penalties |
Essential to reduce penalties and avoid prosecution |
|
Professional Advice |
Strongly recommended |
Strongly recommended |
|
Documentation Required |
Tax returns, invoices, bank records. Multi-year accounts, contracts, offshore details
|
Tax returns, invoices, bank records. Multi-year accounts, contracts, offshore details
|
Useful Tips for COP8 & COP9
- Respond promptly — ignoring HMRC correspondence increases risk.
- Organise your records — invoices, bank statements, payroll, and contracts.
- Understand the type of investigation — COP8 = civil, COP9 = serious/deliberate.
- Consider voluntary disclosure — full disclosure can reduce penalties.
- Seek professional advice early — especially for COP9
- Avoid common mistakes — don’t delay, don’t mix personal and business finances, don’t submit partial or incomplete disclosures.
- Stay calm and methodical — focus on facts, evidence, and timelines.
Final Thoughts
COP8 and COP9 investigations are serious, but manageable with preparation and our expert support.
Key takeaways:
- Respond quickly and organise your records.
- Make full voluntary disclosures where required.
- Seek our professional guidance for complex or multi-year cases.
- Transparency and timely action are your strongest defences.
How can Accounts Tax Group help?
Facing an investigation into your tax affairs by HMRC can be daunting, time consuming and costly.
Call us for a no obligation conversation to discuss your tax problem and see if we can assist.
We are on your side and we will protect your interests when dealing with HMRC.
Ask us for help today
020 8499 8065
Don't Delay
Delays only make matters worse. Our team are on your side and work with HMRC every day, helping our client resolve their tax issues.