Date posted: 16th Jun 2025
If you’ve not yet filed your 2023/24 Self Assessment tax return, it’s vital to act quickly—daily penalties of £10 are now being charged by HMRC for each day the return remains outstanding.
This comes in addition to the initial £100 late filing penalty that applied from 1 February 2025.
Key Dates and Penalties to Be Aware Of
Here’s how the late filing penalties for the 2023/24 tax year stack up:
| Deadline | Penalty |
| 31 Jan 2025 | Filing deadline (online returns) |
| 1 Feb 2025 | £100 fixed penalty issued |
| 1 May 2025 | £10 daily penalty begins (up to 90 days = max £900) |
| 1 Aug 2025 | 5% of tax due (or £300 if higher) |
| 6 Months Late | Further 5% penalty (or £300 if higher) |
| > 12 Months Late | Additional penalties will apply. |
As of June 2025, if your return is still outstanding, you’re likely accumulating £10 per day in penalties, up to a maximum of £900. In addition, late payment penalties and interest may also apply.
What Should You Do If You’ve Missed the Deadline?
If your 2023/24 return is late and penalties are building up:
- File your return as soon as possible – this will immediately stop further daily £10 penalties.
- Pay any tax due to avoid further interest and late payment surcharges.
- If there’s a reasonable excuse (e.g. serious illness, bereavement), consider an appeal—but these are only accepted in specific, well-evidenced cases.
- Seek advice if your affairs are complex or you’re unsure what’s outstanding.
Why It Matters
In addition to the financial cost, late returns can also trigger:
- Increased HMRC scrutiny or enquiry
- Restrictions on accessing time-to-pay arrangements
- Issues with mortgage applications or financial disclosures
Don’t let an overlooked deadline turn into an unnecessary and costly problem.
Help is at hand
If you’re behind on your return or have received penalty notices, we can help you:
- Get up to date with HMRC quickly and efficiently
- Review if penalties can be appealed or reduced
- Understand your tax position and avoid future issues
Contact us today to get your 2023/24 return filed and stop the penalty clock.
