Guide
Code of Practice 9: the serious end, explained without drama
Updated
COP9 is the one category of HMRC letter where "get a specialist" is not upselling but the plain consensus of everyone who works in this field, including HMRC, whose own code recommends professional advice. Here is what it is, calmly.
What COP9 is
Code of Practice 9 is HMRC's procedure for cases where it suspects serious tax fraud. The recipient is offered the Contractual Disclosure Facility (CDF): admit the deliberate conduct, make a complete disclosure of all tax irregularities, and cooperate, in exchange for HMRC not pursuing a criminal investigation into the disclosed conduct. HMRC publishes the code itself (gov.uk) and guidance on the CDF (gov.uk). The offer has a deadline, stated in the letter, and the choice made in that window shapes everything after it.
COP8, the quieter sibling
Code of Practice 8 covers HMRC's Fraud Investigation Service cases that are not started under the fraud suspicion of COP9: typically complex avoidance or significant unpaid tax without an allegation of dishonesty. It carries no CDF offer. COP8 cases are serious and specialist territory too, but they are a different procedure with different stakes, and a COP8 letter should not be read as an accusation of fraud.
Why fees are higher here, and worth it
- The disclosure must be complete: the CDF's protection covers what is disclosed; a materially incomplete disclosure can void the arrangement, which is why specialists manage the report's scope so carefully.
- The stakes include penalties at the top of the range: deliberate and concealed behaviour can draw penalties up to 100% of the tax (higher for some offshore matters), so the penalty negotiation alone justifies experienced representation.
- Fees reflect this: COP9 representation costs substantially more than ordinary enquiry work, scoped per case, typically involving a specialist firm rather than a general practice accountant. Set against a criminal investigation risk, it is the most clearly justified professional fee in this field.
- Fee protection insurance will not cover it: fraud cases are a standard exclusion, see the insurance guide.
If a COP9 letter has arrived
- Note the response deadline in the letter and treat it as fixed.
- Speak to a COP9-experienced specialist before responding at all, including before any well-meaning call to HMRC; initial consultations are commonly free.
- Say nothing speculative to anyone in the meantime: decisions here are strategy, and strategy set early is what the specialist is for.
This page describes HMRC's published procedures; it is not legal or tax advice, and COP9 decisions should be made only with a specialist engaged. For ordinary enquiries and their costs, see the fees guide.