If you earn untaxed income as a self-employed individual or from rental properties, it’s important to complete and submit a self-assessment tax return every year and meet the UK tax return deadline. If you don’t, you could be subject to penalties. On this page, you’ll learn about the updated self-assessment deadline, what may happen if you miss the deadline and the key dates you need to know this tax year.
Filing deadlines: The deadline for submitting your 2022/23 tax return on paper was 31 October 2023, while those filing online had until 31 January 2024
Penalties: If you submit your tax return after the self-assessment deadline, you may be fined £100. The penalty for late submission rises sharply after three months, and continues to climb for prolonged delays
Self-employed: The self-assessment deadline tends to be more important to self-employed people rather than salaried workers, as they’re responsible for paying their own tax
If you need to do a tax return, the deadline for submitting it for the UK tax year 2022/23 (6 April to 5 April) was midnight on 31 October 2023 if you’re submitting your return on paper, or 31 January 2024 if you submitted your return online. (Don’t forget you might also be eligible to claim tax relief when you submit your tax return.)
The only time the tax return deadline in the UK may change is if you receive notice from HMRC telling you to submit an online tax return after 31 October 2023. In that case, you’ll have three months to submit your tax return from the date of notice.
If you still owe tax from your 2021/22 income, it should be settled when you make your first payment.
If you fail to submit your tax return on time, you could receive the following penalties:
HMRC relaxed the late submission rules during the coronavirus pandemic in recognition of the additional pressure facing tax agents and business owners. However, anyone that misses the UK self-assessment deadline for submitting their return or paying any tax owed for 2023/24 will be subject to the usual penalties.
The following are important tax return dates you may want to keep in mind:
The end of the tax year is generally more important for those who are self-employed or registered as a sole trader, rather than people who are employed by companies. This is because self-employed people and sole traders are responsible for paying their own taxes and submitting their earnings through a process called self-assessment.
However, even if you are a salaried employee and earn your income via PAYE (Pay As You Earn), there are also a few instances where you might need to file a tax return, including if you:
Find out whether you need to complete a tax return with our handy guide to the tax return.
The official self-assessment deadline for filing your documents for the tax year ending April 5 (and for paying any money due) is midnight on 31 January. This is always the January after the year in question. So for the 2023/24 tax year (which ends 5 April 2024) you need to file your tax return by 31 January 2025.
You had until 11.59pm on 31 January 2024 to send HMRC an online tax return for the 2022/2023 tax year, which ended on 5 April 2023.