The world of tax is full of deadlines and failing to meet these will often result in penalties. However, whilst HMRC might sometimes suggest otherwise, such penalties are not necessarily set in stone. If you have a good reason for failing to meet a deadline, you can appeal against those penalties and get them cancelled. 

If you are going to appeal against a penalty, then you need to respond quickly. The penalty letter will tell you the deadline for appealing, which will be 30 days in most cases. It is possible to appeal beyond this time period, but it will be much more difficult to do so successfully. Late appeals not only have to justify why you should not have received a penalty in the first place, but also need to explain why the appeal was not sent in more promptly. 

The simplest reason you can give for an appeal is that you did not fail to meet the deadline at all. For this to be successful you will need to provide proof that you filed on or before the deadline date. If you filed a document electronically, an electronic receipt from HMRC will show when this was done. This should either be found within the software you used for filing or as an e-mail sent to you be HMRC immediately after the document was sent. If you sent a document by post then you will need to have used a tracking service showing it was delivered in time. Proof of posting is not generally accepted as proof of receipt. 

An appeal will also usually be accepted if you were not aware of an obligation to file. If HMRC believe you are required to complete a self-assessment tax return, they will issue a notice to file. If this is not received, then you may be able to say that you did not know you needed to complete one. However, this will only work if you did not have good reason to know this would be necessary. If you completed returns in prior years and still have the same income, not receiving a notice to file will not be sufficient to overturn a penalty. 

If you did file late then the task of appealing becomes more difficult. To overturn a penalty where you filed late you need to show you had a “reasonable excuse” why you were unable to meet the deadline. Whilst this term is not precisely defined in law, HMRC does provide a list of issues that they will accept give the taxpayer a reasonable excuse:

• Your partner or another close relative died shortly before the tax return or payment deadline.

• You had an unexpected stay in hospital that prevented you from dealing with your tax affairs.

• You had a serious or life-threatening illness.

• Your computer or software failed just before or while you were preparing your online return.

• Service issues with HMRC online services.

• A fire, flood or theft prevented you from completing your tax return.

• Postal delays that you couldn’t have predicted.

• Delays related to a disability you have.

In contrast, HMRC also provide a shorter list of things they will not accept as a reasonable excuse:

• Not receiving a reminder – if you have an obligation to file with HMRC, you are expected to be aware of the deadlines associated with those filings. Note that reminders are sent subsequent to the notice to file mentioned above.

• Relying on someone else – the obligation to file falls on the taxpayer and he/she is responsible for ensuring it is fulfilled.

• Making a mistake – whilst it can reduce some penalties, carelessness is not a general excuse.


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