Self Assessment (SA) tax penalties: what penalties are due for outstanding tax returns? What penalties are due for late payment? Are there special rules delays affecting victims of the Post Office Horizon scandal and due to Covid-19. 

This is a freeview 'At a glance' guide.

At a glance

Tax penalties apply for the late filing of Self Assessment (SA) tax returns and late payment of tax due under SA. There may also be penalties for failure to notify chargeability and for error if there is a mistake in a return.

Late filing: a key feature of the current regime is that the late filing penalty is not reduced if tax is paid on time, see Late filing a SA return: automatic penalties

Penalties for:

are all tax geared: if no tax is due or outstanding, no penalty applies.

Late filing penalties can be mixture of fixed-rate and tax geared penalties: it depends on your degree of lateness and tax liability.

Interest is charged on both unpaid tax and unpaid penalties.

Late filing and payment: at a glance*

*Note also comments below for special measures due to Covid-19.

Late filing

Late payment


Miss filing deadline




30 days late

5% of tax due

3 months late


Daily penalty £10 per day for up to 90 days (max £900)

6 months late


5% of tax due or £300, if greater*


6 months late

5% of tax outstanding at that date

12 months late


5% or £300 if greater*, unless the taxpayer is held to be deliberately withholding information that would enable HMRC to assess the tax due.


12 months late

5% of tax outstanding at that date

12 months & taxpayer deliberately withholds information


Based on behaviour:

  • deliberate and concealed withholding 100% of tax due, or £300 if greater.
  • deliberate but not concealed 70% of tax due, or £300 if greater.

Reductions apply for prompted and unprompted disclosures and telling, giving and helping.

* Subject to multi penalty rule para 17 schedule 55 FA 2009.

Late filing example:

Note: this example ignores any one-off easements such as for Covid-19 (see below). 

In January 2023 John goes to Australia on a sabbatical and accidentally forgets to file his 2021-22 Self Assessment tax return. This results in a fixed rate tax liability of £100.  He comes home and files his return on 1 February 2024. HMRC sends him notification of penalties as follows:

Trigger date Penalty
Missed filing deadline: 31 Jan 2023 £100
Unfiled after 3 months: deadline 30 April 2023 £10 per day for 90 days
Unfiled after 6 months: deadline 31 July 2023 £300* reduced to £100
Unfiled after 12 months: deadline 31 Jan 2024 £300* reduced to £nil

 *The penalties for being 6 months late and 12 months late are subject to the interaction rule in para 17(3) and taken together they should not exceed 100% of the tax due. See Grounds for Appeal: HMRC error or flaw

Late payment example:

Note: this example ignores any one-off easements such as for Covid-19 (if applicable, see below).

Jane was due to make a balancing payment of £10,000 in Income Tax under Self Assessment for the 2021-22 tax year; it fell due for payment on 31 January 2023. She ignores the reminders and eventually pays her tax in February 2024.

If the tax was not paid penalties accrue as follows:

Trigger date Penalty
Unpaid by midnight 2 March 2023 £500 (5%)
Unpaid by midnight 2 August 2023 £500 (5%)
Unpaid by midnight 2 February 2024 £500 (5%)


Late payment: Time to pay agreements

If the taxpayer makes a Time to pay agreement with HMRC the penalty is suspended.

  • The taxpayer will become liable to the penalty if the suspension agreement is broken.

Special reduction

  • HMRC has a statutory requirement to consider whether any special circumstances exist and if so it may override the statutory penalties and reduce them as it sees fit. See Appeals: Grounds for Appeal Toolkit


  • The taxpayer has 30 days to lodge an appeal with HMRC against a tax penalty. This was extended by three months for COVID-19 related delays for the 2019-20 tax year.
  • A Late appeal may be accepted at the discretion of HMRC or the tribunal judge.

The legislation relevant to each type of penalty provides for the appeal process and it is advisable first off to ensure that any penalty charged has been made correctly according to the legislation.

HMRC will not challenge any late filing penalty appeal provided that there is a Reasonable excuse for late filing and that an appeal has been made.

Appealing a penalty can be far from straightforward as there are numerous grounds for appeal and technical arguments that can assist the taxpayer.

Post Office Horizon Scandal compensation 

  • HMRC has confirmed that postmasters who have not received a top-up payment and tax advice grant from the Post Office in time to file their return and pay their tax by 31 January 2024 will be able to claim that they have a reasonable excluse for filing their returns or paying their tax late.
  • HMRC has a deadicate support team who can advise further on the tax status of compensation payments.
  • See 

Penalties and COVID-19 


HMRC confirmed that:

  • Returns for 2019-20 may be filed late: up to 28 February 2021 without incurring a penalty.
  • In a separate announcement, they confirmed that Self Assessment taxpayers would not be charged the usual 5% late payment penalty provided that they paid their tax or set up a payment plan by 1 April 2021.
  • They will allow appeals to be made up to three months late as a result of COVID-19 being a reasonable excuse for the compliance failure.  See COVID-19: Tax appeals deadline.


HMRC confirmed that:

  • Returns for 2020-21 may be filed late: up to 28 February 2022 without incurring a penalty.
  • Self Assessment taxpayers would not be charged the usual 5% late payment penalty provided that they paid their tax or set up a payment plan by 1 April 2022.
  • See 30-day penalty waiver for 2020-21 tax return filing & payment

Daily penalties: developments

Small print

The legislation is found in Schedule 24 FA 2007, Schedule 41 FA 2008 and Schedules 55 and 56 FA 2009.

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