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HMRC · COP8 vs COP9 · 2026/27

HMRC Code of Practice 8 vs 9 (2026/27)

Code of Practice 8 and Code of Practice 9 are HMRC's most serious investigation routes. COP8 deals with suspected tax avoidance — using arrangements HMRC considers ineffective. COP9 deals with suspected tax fraud — deliberate deception. Both carry serious financial and reputational consequences. This guide explains what triggers each, what they involve, and the critical role of the Contractual Disclosure Facility in COP9 cases.

5-minute read

COP8 vs COP9 in one paragraph: these are HMRC's most serious civil investigation procedures. COP8 is reserved for suspected use of tax avoidance arrangements — typically marketed schemes HMRC believes don't work. COP9 is reserved for cases where HMRC suspects deliberate tax fraud. Both are civil, not criminal — but COP9 specifically OFFERS immunity from criminal prosecution in exchange for full and complete disclosure via the Contractual Disclosure Facility. Receiving either letter means your case has been escalated by HMRC's risk teams. Professional representation is essential.

Code of Practice 8 — suspected avoidance

COP8 is HMRC's civil investigation procedure for suspected tax avoidance, particularly:

Key features of COP8:

Most COP8 cases settle through negotiation, with the disputed arrangement unwound and tax/penalties paid.

Code of Practice 9 — suspected fraud

COP9 is HMRC's most serious civil investigation procedure, used where they suspect deliberate fraud. Critically, it offers an opportunity to avoid criminal prosecution via the Contractual Disclosure Facility.

Triggers for COP9:

Receiving a COP9 letter is serious — it means HMRC's specialist team has reviewed evidence and concluded fraud is suspected. The letter typically:

The Contractual Disclosure Facility (CDF)

The CDF is the heart of COP9. Mechanics:

  1. You sign an Outline Disclosure within 60 days of the COP9 letter, identifying all areas of suspected deliberate non-disclosure
  2. You then prepare a full disclosure report, typically taking 6-12 months
  3. HMRC reviews the disclosure and computes tax, interest, and penalties
  4. Settlement is reached, typically with civil penalties up to 100% of the tax
  5. In exchange: immunity from criminal prosecution for the matters disclosed

Critical points:

The difference in stakes

FeatureCOP8COP9
HMRC suspectsAvoidance (arrangement that doesn't work)Deliberate fraud
Criminal exposureLow (civil)High if CDF declined
Penalty rangeCivil, scheme-dependent (often 30-70%)Up to 100% civil; or criminal prosecution if declined
Time to respondReasonable (typically 30 days for first response)60 days for CDF acceptance
Professional adviceStrongly recommendedEssential
OutcomeCivil settlement, arrangement unwoundCivil settlement + tax + penalty; OR criminal referral

The cost of getting professional advice

Professional representation in COP8/COP9 typically costs:

This sounds extreme but the stakes justify it. A typical COP9 case involves £100,000+ of tax and penalties. Professional advice usually saves multiples of its cost through:

What happens if you decline CDF

If you decline the CDF (or fail to respond within 60 days), HMRC's response options:

Criminal prosecution for tax fraud carries serious consequences: imprisonment (up to 7 years for cheating the public revenue), confiscation orders, disqualification from holding company directorships, reputational damage.

The "denying" trap

A common mistake: telling HMRC "I haven't done anything wrong" in response to a COP9 letter.

If you sign a CDF Outline Disclosure claiming there's nothing to disclose, and HMRC subsequently proves there was, the CDF immunity is gone AND you have a fresh charge of providing false information.

If you genuinely believe you've done nothing wrong, the right path is:

  1. Engage professional advice immediately
  2. Review the COP9 letter and HMRC's stated concerns thoroughly
  3. Decline the CDF formally and engage with the ensuing investigation
  4. Defend factually with full cooperation

Never sign a Certificate of Tax Position or CDF Outline making sweeping denials without rigorous review.

Common COP8/COP9 mistakes

Sources

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