Appeal HMRC Late Filing Penalties

Complete guide to appealing self-assessment penalties. Learn the reasonable excuse defence under Taxes Management Act 1970 s.118(2), 30-day appeal window, HMRC internal review, and tribunal rights.

Quick Answer

If HMRC issues a late filing penalty on your self-assessment tax return, you can appeal within 30 days citing "reasonable excuse." Reasonable excuses include: illness, death in family, IT failure, professional advisor error, or unexpected event outside your control. HMRC must accept your excuse or you proceed to tribunal (free filing). Tribunals overturn penalties in about 40% of cases where reasonable excuse is proven. You must appeal in writing within 30 days or lose the right to challenge. First step: request HMRC internal review (also free). If they refuse, appeal to tribunal. This is free to do yourself; no solicitor needed.

How to Appeal HMRC Penalties

1

Gather Evidence of Reasonable Excuse

Collect proof of your excuse: medical letters for illness, death certificate for bereavement, IT support confirmation for system failures, email from accountant admitting error, or documentation of unexpected circumstances. Write detailed account: when did issue occur? When did you discover the late filing? What steps did you take to comply? Keep all supporting documents.

2

Appeal Within 30 Days (Written)

Send written appeal to HMRC within 30 days of penalty notice. State clearly: (a) you dispute the penalty, (b) your reasonable excuse with all supporting evidence, (c) request review under TMA 1970 s.49B. Send via registered mail or email (keep proof of delivery). Do not pay the penalty yet. Make your case clear and concise; include a timeline of events.

3

HMRC Internal Review or Tribunal Appeal

HMRC reviews within 45 days. If they accept your excuse, penalty is cancelled. If refused, you can appeal to tribunal (Upper Tribunal or First-Tier depending on penalty amount). Tribunal filing is free. You present evidence; judge decides if excuse is "reasonable." No legal representation needed. Tribunals are more lenient than HMRC; many penalties are overturned if you have any credible excuse.

What the Law Says

Taxes Management Act 1970, s.118(2) (Reasonable Excuse)
A taxpayer is not liable to a late filing penalty if they can show reasonable excuse for the late filing. "Reasonable excuse" is not defined by statute but includes: illness, bereavement, unforeseeable events, system failures, and professional advisor errors. The test is objective: would a reasonable person in your circumstances have filed on time? Courts favour taxpayers who made genuine efforts to comply.
Finance Act 2009, Sch.55 (Penalty Regimes)
Self-assessment filing penalties: 5% of tax due if filed 3-12 months late, 10% if filed 12+ months late. These are automatic; HMRC does not need to prove deliberate wrongdoing. The only defence is reasonable excuse. Penalties are capped at the tax owed. You can appeal to reduce or cancel them.
Taxes Management Act 1970, s.49B (Internal Review)
You can request an internal review of HMRC's penalty decision. The review is free and takes 45 days. If HMRC refuses to review or upholds the penalty, you can appeal to tribunal. Internal review is a mandatory step before tribunal; you cannot skip it (unless you want tribunal's decision without review).
First-Tier Tribunal (Tax Chamber) Procedure
If HMRC refuses your appeal after review, you can appeal to tribunal (no fee). You submit evidence and explanation; HMRC submits its position. The judge decides if your excuse is reasonable. Tribunal decisions are binding on HMRC; appeals are only possible on points of law (very rare). Most tribunal decisions are final.

Common Reasonable Excuse Scenarios

Illness or Hospitalisation

You were seriously ill/hospitalised around the filing deadline. Medical evidence: hospital discharge letter, GP confirmation, medication records. Courts accept genuine illness as reasonable excuse if it prevented filing. Must file appeal with medical proof within 30 days.

Death in Family

Death of spouse/close relative near deadline caused distress/inability to file. Death certificate plus evidence of your connection to deceased. Courts readily accept bereavement as reasonable excuse, especially if you are named executor or main mourner.

Computer System Failure

Your accountant's system failed; data lost; could not regenerate return in time. Email from accountant confirming system failure, timeline of recovery. HMRC often accepts system failure if accountant error contributed; you may share liability with them.

Accountant or Advisor Error

Your accountant was supposed to file your return but failed to do so. You relied on their assurance. Letter from accountant admitting error. Courts accept reasonable reliance on professional advisors. This is one of the strongest excuses.

Absence from UK (Unforeseeable)

You were unexpectedly abroad (emergency abroad, hospitality staff, military) and unable to file. Passport stamps, employer confirmation, or travel documentation. Courts accept genuine unforeseeable absence if you took steps to return/file upon return.

HMRC Website/System Down

HMRC's online filing system was unavailable on filing deadline or immediately before. Evidence: HMRC confirmation of outage, screenshots, news reports. HMRC sometimes accepts this but rare; you may argue shared responsibility.

Frequently Asked Questions

How long do I have to appeal HMRC penalties? +
30 days from the penalty notice. This is strict; missing the deadline usually means you lose the right to appeal. Write to HMRC immediately upon receiving penalty notice. Send via registered mail so you have proof of timely delivery.
What counts as "reasonable excuse"? +
Illness, bereavement, system failure, unforeseeable events, professional advisor error, or other circumstances beyond your control. Vague excuses ("I forgot," "I was busy") are weak. You must show a genuine barrier to filing and that you took steps to comply once able.
Can I appeal after paying the penalty? +
Yes. Paying the penalty does not waive your appeal right. You can appeal within 30 days of penalty notice regardless of payment. If you win appeal, HMRC refunds the penalty. Do not delay appealing just because you paid.
What if HMRC refuses my appeal after internal review? +
You can appeal to the First-Tier Tribunal (free filing fee). Tribunal is more independent and lenient than HMRC. About 40% of appeals succeed at tribunal even if HMRC refused. Tribunal judges can overturn HMRC's decision.
Do I need a solicitor or accountant to appeal? +
No. You can appeal yourself in writing. Most self-assessment penalty appeals are straightforward. An accountant (£200-£500) can help gather evidence; a solicitor is rarely needed unless the case is complex or you lose at tribunal and want to appeal to Upper Tribunal.
How much is the HMRC penalty for late filing? +
5% of tax due if filed 3-12 months late; 10% if filed 12+ months late. Penalties are capped at the tax amount owed. For example, if your tax bill is £1,000 and you filed 6 months late, penalty is £50 (5% of £1,000).

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