Appeal Letter Template

HMRC Penalty Appeal Letter Template

Below is an example of how a professional HMRC penalty appeal letter should be structured. A strong appeal letter cites the correct legislation and addresses the legal test for reasonable excuse.

What a good appeal letter includes

  1. Your details — full name, address, UTR, National Insurance number
  2. HMRC's address — Self Assessment, PO Box 4000, Cardiff, CF14 8HR
  3. Subject line — referencing your penalty reference, tax year, and UTR
  4. Opening statement — "I am writing to formally appeal the penalty..."
  5. Legal framework — cite Finance Act 2009 Schedule 55 (or 56 for late payment)
  6. Reasonable excuse — detailed explanation of what happened
  7. Perrin v HMRC test — demonstrate that your excuse meets the legal test
  8. Prompt action — explain what you did once the excuse ended
  9. Request — formally request cancellation of the penalty
  10. Evidence list — list any supporting documents attached

Example letter structure

[Your Name]
[Your Address]
[Your Postcode]


HM Revenue & Customs
Self Assessment
PO Box 4000
Cardiff
CF14 8HR


[Date]


Re: Appeal Against Self Assessment Late Filing Penalty
UTR: [Your UTR]
National Insurance Number: [Your NI Number]
Penalty Reference: [From SA326D]
Tax Year: [e.g. 2024/25]


Dear Sir or Madam,


I am writing to formally appeal the above penalty issued under Schedule 55 of the Finance Act 2009 for the late filing of my Self Assessment tax return for the [tax year] tax year.


Reasonable Excuse

[Detailed explanation of your circumstances, including specific dates, what happened, why it prevented you from filing, and any evidence you have.]


Legal Basis

In accordance with the test established in Perrin v HMRC [2018] UKUT 156, I submit that: (1) the facts set out above constitute a reasonable excuse; (2) the excuse persisted throughout the period of default; and (3) I acted as soon as reasonably possible once the excuse ended, filing my return on [date].


I therefore respectfully request that the penalty of £[amount] be cancelled in full.


Yours faithfully,

[Your Name]

Common mistakes to avoid

  • Being too vague — "I was ill" without dates or evidence
  • Not citing legislation — makes it look like an informal complaint
  • Missing the Perrin test — HMRC officers are trained to apply this test
  • Appealing late without explanation — if past 30 days, explain why
  • Blaming HMRC without evidence — be factual, not emotional

Get a personalised appeal letter

This template shows the structure. TaxFlip writes the actual letter tailored to your specific penalty, excuse, and circumstances — citing the exact legislation and case law.

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