Penalties: Not Football, Tax Returns!

Self Assessment Tax Return Deadline 31st January 2019

With just over 6 months until the 2018 self assessment tax return deadline (31st January 2019), you may not have even begun to think about it. With the summer we’ve been having that’s hardly surprising! However, you should always be aware of the penalties you could face should your tax return be late.

Help Me With My Self Assessment

If you need a hand with your self assessment tax return contact us for a free meeting to discuss your situation and how we may be able to help now and in the future.

Late filing

If your tax return is up to 3 months late you may face a penalty of £100.

Between 3 and 6 months late will result in a daily penalty of £10 per day for up to 90 days.

Filing between 6 and 12 months late is a penalty being the greater of 5% of your tax due or £300.

A return filed more than 12 months late is again 5% or £300 unless you are found to have deliberately withheld information.

If you have deliberately withheld information, the penalty is based on whether the withheld information was concealed or not concealed. If concealed, a penalty of 100% of tax due or £300 if greater will be payable. However, if not concealed, the penalty is 70% of tax due or £300. Reductions can be applied for prompted and unprompted disclosures.

Late payment

Interest is charged on a daily basis on both tax due and tax penalties payable.

A payment made 30 days late will incur a penalty of 5% of your tax due.

Up to 6 months late results in a penalty of 5% of tax outstanding at that date.

If your payment is 12 months late, the penalty is 5% of tax outstanding at that date.


You can appeal against a penalty if you have a reasonable excuse.

Examples of reasonable excuses include:

  • An unexpected stay in hospital that prevent you from completing your tax return
  • A serious or life threatening illness
  • A fire, flood or theft


Find more examples from HMRC here along with excuses which will not count as reasonable.

Read our blog on Excuses and Expense Claims: What not to submit