It’s imperative to know as much as possible about the tax return before the end of January. We don’t just mean the actual date itself either; there are details to consider for the exact status of your Self Assessment, as well as how to make it pitch-perfect for HMRC.
Read on for all the critical information you’ll need to know ahead of the UK’s tax return deadline day 2024.
WHAT ARE THE UK TAX YEAR DATES AND FILING DEADLINES?
- The tax year runs from the 6th April 2023 – 5th April 2024. Your accounts need to be calculated according to these dates. You can start submitting your tax return on the first day of the next tax year 6th April.
- 31 July: when your second payment on account becomes due.
- 31 October: the deadline for paper filing of tax returns
- 30 December: If you are also employed, you can choose to pay any tax due through your PAYE code, instead of making a big payment on 31 January, but only if you submit your tax return before 30 December.
- 31 January: The deadline for online self-assessment filing. It is also the deadline for paying any income tax due, Class 4NIC and your first payment on account for next year.
WHAT IF YOU MISS THE CUT-OFF DEADLINE?
The tax return deadline 2024 is unforgiving. If you miss the 31st January date, you’ll be handed an instant £100 penalty. One of two things may happen:
- If you haven’t paid the tax, you have 30 days to satisfy the bill. Afterwards, 5% interest is charged on it.
- A late return of 90 days or more incurs a £10 a day penalty on top of your outstanding bill, for a maximum of £900 over 90 days. After six months, it’s a further £300 fine or 5% of your tax owing – whichever is greater. When you get to 12 months after the Self Assessment date, and it still hasn’t been submitted, that’s another £300 or 5% of your tax owing on top of what you already owe.
Other penalties can be issued if HMRC suspects you’ve misled them on the Self Assessment. Tax investigations are launched in this case. Total, 100% accuracy is key to avoid the taxman breathing down your neck.
HOW DO I AVOID MISSING THE TAX RETURN DEADLINE?
There’s still time to prepare a submission before the tax deadline 2024. Take advantage of our time-saving tool, GoSimpleTax, designed for your peace of mind and ease of use. We’ve built a platform that connects you straight to HMRC, collecting every receipt, invoice and bank statement. Start your free trial today.
Blog content is for information purposes and over time may become outdated, although we do strive to keep it current. It's written to help you understand your Tax's and is not to be relied upon as professional accounting, tax and legal advice due to differences in everyone's circumstances. For additional help please contact our support team or HMRC.

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