HMRC was expecting 12.2m 2022/23 returns and received 11.6m by the 31 January 2024 deadline, suggesting that 0.6m returns will be late. However, the number received includes about 0.5m voluntary returns and late registrations, so the number missing the deadline is estimated at 1.1m. This compares with a figure of 1m for 2021/22 (the figures do get revised as further analysis is done).

The number of taxpayers required to file a self assessment (SA) tax return has continued to grow. More taxpayers have been drawn into the system by the impact of higher interest rates and the freezing and reduction of bands and allowances. The record number of returns filed is a considerable achievement by all concerned, especially given the closure of the HMRC SA helpline in Summer 2023 and recent restrictions.

Those who missed the deadline should take action as follows:

• File the return as soon as possible, ideally before daily penalties start to be incurred, usually on 1 May.
• Some taxpayers may not meet the criteria for filing a 2022/23 tax return, for example where their circumstances have changed. In such cases the return needs to be formally withdrawn by contacting HMRC. Taxpayers can do this by completing an online form. The online form is not available to agents, who need to use webchat, phone or post. If a return is withdrawn, any late filing penalty is automatically cancelled. 
• Some taxpayers may not yet be registered for self assessment and will be waiting for their unique taxpayer reference to allow them to file. Taxpayers have three months and seven days from the date of their notice to file before they are at risk of a late filing penalty. However, they may be at risk of a penalty for late notification.
• Pay the tax due or make a payment arrangement. Interest charges at 7.75% apply to any balance on a payment plan, getting the plan in place before 1 March 2024 will avoid a 5% late payment penalty on top of that.

Those who filed a return using provisional figures so they met the deadline have until 31 January 2025 to amend their return but should do so as soon as possible.

Penalties and reasonable excuse

HMRC will issue £100 late filing penalties to all those who missed the deadline. These are usually received by taxpayers between mid-February and mid-March. Where a return is not required it should be formally cancelled (as noted above), an appeal against the penalty is not the correct course of action.

Points to consider when making an appeal include:

• The return must have been filed before HMRC will consider an appeal.
• The appeal should normally be made within 30 days of the penalty notice, but late appeals will sometimes be considered.
• There should be a reasonable excuse for late filing.
• Taxpayers can make the appeal online.
• Agents will need to use the paper form SA370 or write.

The reasonable excuse must continue throughout the period from the missed filing date until shortly before the return is filed. If it is accepted that reasonable excuse applied for some, but not all, of this period, the penalties will not be cancelled.

HMRC takes a narrow view of what is a ‘reasonable excuse’. HMRC’s view can be found here.

If HMRC turns down the appeal, you can request a review. The next step is an appeal to the First-tier Tribunal (Tax). This can be done at an oral hearing or on paper, but the taxpayer always has the right to appear and be heard.

The tribunal may, in some cases, take a wider view of what is a reasonable excuse. For example, the tribunal may accept that you had a reasonable excuse if you relied on your accountant or other third party, something that HMRC will not usually consider.