Can you appeal an HMRC penalty? What counts as a reasonable excuse?

You can challenge an HMRC penalty if you think it is wrong or you had a reasonable excuse for failing to meet the obligation. The useful question is not whether the circumstances were unpleasant. It is whether they reasonably prevented this taxpayer from filing, paying or acting on time.

HMRC's public guidance says you normally have 30 days from the date the penalty was issued to contact HMRC or appeal.

Deal with the missed obligation as well as the appeal

If a tax return is still outstanding, file it. If a payment can now be made, pay it or address the debt.

HMRC's reasonable-excuse guidance expects taxpayers to put matters right as soon as they are able after the excuse ends.

An appeal is not a licence to leave the underlying problem untouched while correspondence slowly reproduces in a drawer.

Examples HMRC says may be reasonable

HMRC's current public guidance gives examples including:

• death of a partner or close relative shortly before the deadline;
• an unexpected hospital stay;
• serious or life-threatening illness;
• computer or software failure while preparing an online return;
• problems with HMRC online services;
• fire, flood or theft;
• unexpected postal delays;
• delays connected with disability or mental illness;
• being unaware of or misunderstanding a legal obligation;
• relying on another person to submit a return where they failed to do so.

This is not a checklist where ticking one box guarantees success.

HMRC's own internal guidance says what is reasonable can differ between taxpayers because their individual abilities and circumstances differ.

Evidence and chronology matter

A stronger appeal usually explains:

1. what the tax obligation was;
2. the deadline;
3. what happened;
4. when the problem began;
5. why it prevented compliance;
6. when the problem ended;
7. when you actually filed, paid or otherwise corrected the position;
8. what evidence supports the explanation.

A vague statement such as “I was unwell that year” is weaker than a dated explanation showing how illness affected the filing period and when you were able to deal with the return again.

What HMRC says normally does not count

HMRC gives examples of circumstances it will not normally accept, including:

• a cheque or payment failing because there was not enough money;
• finding HMRC's online system too difficult;
• not receiving a reminder from HMRC;
• simply making a mistake on the tax return.

These examples do not mean financial hardship or a mistake can never be relevant to any other tax issue. They mean those facts alone do not normally establish reasonable excuse for the missed obligation.

What if someone else was supposed to file?

HMRC's current public guidance recognises that relying on someone else who failed to submit can potentially be relevant.

But the circumstances still need explaining. Questions may include:

• who was responsible for filing;
• why it was reasonable for you to rely on them;
• what instructions and information you provided;
• whether you followed up;
• when you discovered the failure;
• how quickly you corrected it.

The existence of an accountant does not automatically transfer every statutory responsibility away from the taxpayer.

What if the appeal itself is late?

A late appeal is not necessarily impossible. HMRC says that if you miss the normal appeal deadline you will need to explain why.

This creates two separate timing questions:

• was there a reasonable excuse for the original tax failure?;
• why was the penalty appeal not made on time?

Deal with both rather than assuming one explanation automatically covers the other.

Check whether the penalty is technically right

Not every appeal depends on reasonable excuse.

A penalty can also be challenged because it should not have been issued or was calculated incorrectly. Check:

• whether the filing or payment deadline was correct;
• whether HMRC received the return earlier than its system shows;
• whether the penalty relates to the correct tax year;
• whether payments were allocated correctly;
• whether an amended HMRC record should have caused a penalty to be cancelled.

What to gather before asking for help

Have:

1. the penalty notice;
2. the date it was issued;
3. the underlying tax return or payment deadline;
4. the date you actually complied;
5. a short timeline of the circumstances relied on;
6. evidence such as hospital records, service outage messages, correspondence or adviser communications;
7. earlier appeals or HMRC responses.

A good penalty appeal is usually a short factual argument supported by a clean timeline, not a 14-page essay about how unfair HMRC feels in principle.