What is the UK tax return deadline?

Your Self Assessment tax return deadline is 31 January for the tax year that ends the year before. That’s if you submit your return online. But for those submitting a paper return, the deadline is 31 October. (There are some exceptions here, such as if you’re the trustee of a registered pension scheme or a non-resident company, where the deadline is also 31 January.)

Not meeting your UK Self Assessment deadlines can result in interest and penalties, so it’s worth understanding the timeline. We’re here to help you do that. 

In this article, we’ll take you through all the dates and details you need to know.

All you need to know about self-assessment tax return filing deadlines

You need to submit a Self Assessment tax return if you have any income other than what is automatically deducted from your wages and pension.

This could be income from:

• Being self-employed
• A business partnership
• Tips and commission
• Renting out a property
• Savings and investments 
• Overseas
• Selling something that increased in value

You will also need to send a tax return if you’ve opted to pay the High Income Child Benefit Charge. If you still get the Child Benefit but you or your partner now have an income of over £60,000, you can opt to stop receiving the grant or continue receiving the benefit and pay a tax charge. To pay the tax charge, you will have to send a tax return.

Once you know whether you have to submit, the next step is knowing when to submit. Read on for all the important dates to mark on your calendar.

Your Self Assessment tax return timeline

The tax year runs from 6 April to 5 April.

If you need to file a Self Assessment tax return, it’s important to keep a record of your financial transactions over that time.

If this is your first Self Assessment tax return

If you’ve never filed a Self Assessment tax return, your first step is letting the HMRC know that you plan on doing so.

You must register by 5 October for the year that ends that April. Here’s where to do that.

If you have registered but have not filed a return, you will have to register again to reactivate your account.

Once you have registered, you will receive a confirmation by post of your registration with your 10-digit Unique Taxpayer Reference (UTR). It usually takes between 10 to 14 working days to get this confirmation. You can use this tool to see when you can expect a reply from HMRC.

You will also be able to find your UT in your:

• Personal Tax Account which you can set up here
• The HMRC app which you can get here

Once you are registered, you can send a Self Assessment tax return.

If you have filed a Self Assessment Tax Return before

Once the tax year ends on 5 April, you can submit your tax return for that year.

You then have until 31 January of the following year to file without incurring penalties and interest.

Filing in the first week of the new tax year will make you an early bird. (For the 2023/24 tax year, 300,000 taxpayers did so!)

Getting it done early can avoid the stress of having to get it in at the last minute. And there are other perks too. It helps with budgeting for the upcoming tax year. It also means that any overpaid tax bills will be refunded sooner as they are processed as soon as your return is in.

When is the deadline for your tax return?

Whether you have just registered or have sent in a return in the past, the deadline is the same for filing: Midnight on 31 January following the end of the tax year (5 April). If you file online, you’ll see your bill in your account straight away.

Remember, however, that if you wish to file a paper return, you must get it in by midnight on 31 October on the same calendar year that the tax year ended if you wish to avoid penalties.

Deadlines for paying your tax bill

The deadline for paying tax you owe is midnight on 31 January following the end of the tax year (5 April) — the same deadline for submitting an online tax return. 

That means that to avoid penalties and interest, you have to both submit and pay any outstanding amounts by midnight on 31 January. The deadline for payment is the same whether you submit a paper or online return.

You may also have a second deadline to be aware of halfway through the calendar year — midnight on 31 July — if you make what’s called “payments on account”. Payments on account allow you to divide up your tax bill into two instalments based on the estimation that HMRC makes on your previous financial year. 

HMRC will let you know if you need to make payments on account. You will likely need to make payments on account if 80% of your income is not taxed at source and needs to be processed through a Self Assessment tax return or because you had a tax bill higher than £1,000.

Tax return deadline FAQs

What tax year is due in January 2025?

Your 2023/24 Self Assessment tax return is due in January 2025.

That’s because:

• The tax year starts from 6 April every year and runs to 5 April.
• Your Self Assessment tax return is due on 31 January the following year.

When to submit your tax return for 2024-2025

For the 2024/25 tax return it works as follows:

• The tax year runs from 6 April 2024 to 5 April 2025 
• The deadline to submit your tax return is 31 January 2026

What should you do if you need to change your return?

It’s possible to make changes to your return once you’ve filed it. If you need to change it:

• Within 12 months of the Self Assessment deadline, you can change your return by submitting another one, either online or on paper. You need to wait at least 72 hours before filing an updated return. 

You’ll be able to see your updated bill straight away. If you’ve overpaid, you may be able to claim a refund here.

If you need to pay in, your new bill will should our deadline.

• More than 12 months after the deadline, you’ll need to contact the HMRC in writing. Here’s how to contact them. 

If you need get a refund because you’ve overpaid, you can claim up to 4 years after the end of the relevant tax year.

What should you do if you no longer need to file a return?

If you  think you no longer need to send a return because your income has changed, it’s important to let the HMRC know before the Self Assessment deadline (31 January).

You can do this by:

• Signing into your HMRC online services account and filling in an online form.
• Online through the HMRC digital assistant
• Phone: 0300 200 3310
• Post: Self Assessment, HM Revenue and Customs, BX9 1AS, United Kingdom

The HMRC will send you a letter confirming that you don’t have to submit a return for that financial year.

What is the penalty for filing a tax return late?

If you file your tax return late or make a late payment, you’ll have to pay a penalty. If you file more than three months late, the penalty is £100. This increases if it’s more than six months late.

You can use this tool to estimate your penalties for late filing and payment.

If you have a valid reason for filing or paying late, such as illness, fire or flood, or a death in the family, you can challenge your penalty here.

Note that technical challenges such as a crashed computer or having trouble with HMRC’s online service may also count as reasonable excuses.

You typically have 30 days to appeal after a penalty has been issued.

What should you do if you need help with your tax return?

If you need help filing your return, you have various options:

• Contact HMRC through their:
• Digital assistant — HMRC suggests that this is the quickest way to get a response
• Contact line (0300 200 3310 from the UK between 8 am and 6 pm, Monday to Friday)
• Twitter account: @HMRCcustomers
• Postal address: Self Assessment, HM Revenue and Customs, BX9 1AS, United Kingdom 
• Hire a professional accountant or tax adviser. It’s important to let HMRC know that you’ve hired someone to deal with your tax on your behalf.
• Use a “trusted helper”. That’s a family member or friend who you give permission to do your taxes for you. You’ll need to let HMRC know about this too.
• Get free professional advice for lower income people. There are charity services available for those in lower income brackets, including TaxAid and Tax Help for Older People.

Tax return deadlines: quickfire summary

Here’s your Self Assessment tax return filing deadline cheat sheet:

• The tax year runs from 6 April to 5 April.
• If you’ve never submitted a tax return before, the deadline to register is 5 October for the tax year that ends on 5 April of that calendar year.
• The deadline to submit an online return is midnight on 31 January following the end of the tax year.
• The deadline to submit a paper return is midnight on 31 October following the end of the tax year.
• The deadline to pay what you owe on your return is midnight on 31 January following the end of the tax year.
• If you need to make payments on account, the deadline is midnight on 31 July following the end of the tax year.

Disclaimer: The information provided in this article about tax returns is for general informational purposes only. It does not constitute formal financial advice. Readers are strongly encouraged to consult with a qualified financial adviser to obtain advice tailored to their specific circumstances and financial goals.

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