What is the due date for filing self-assessment tax returns?

Are you unsure about whether you need to file a tax return? HMRC's online tool can help you check.

For those who are required to file a self-assessment tax return, it's important to be aware of the deadlines. More than 12 million people must file a self-assessment tax return every year.

The deadline to file your 2024/25 tax return online is 31 January 2026. However, if you submit a paper tax return, the documentation needs to be with the taxman by midnight on 31 October.

Self-employed workers, buy-to-let landlords, investors, and those paying back Child Benefit are among those who must file a self-assessment tax return.

If your tax bill for 2023/24 was £20,000, you will be required to make two payments on account, worth £10,000 each, for the 2024/25 tax year. These payments are due, with the first payment on account due by 31 January, while the second must be paid by 31 July.

Remember, the January deadline is also when you need to pay any outstanding income tax.

If you believe your tax bill is likely to be lower than the previous tax year, you can apply to have your payments on account reduced.

Registering to file a tax return can take a while, since you're relying on the postal service to send you a Unique Taxpayer Reference (UTR) number. The deadline to register for self-assessment is 5 October.

It's crucial you take the time to gather together all the relevant paperwork before you start attempting to fill in the return, such as payslips, details of other income sources, savings and investments, pension contributions, and charitable donations. Understanding the tax allowances and tax reliefs that apply to you means you may be able to reduce the actual tax you have to pay.

If you make a mistake with your tax return, you can correct it within 12 months of the tax return being filed, with a new tax bill due on the updated return. You will need to wait at least 72 hours after filing your return to make any changes.

If HMRC was expecting a tax return from you and you missed the deadline, you will be subject to financial penalties and interest on any unpaid tax.

It's always best to stay on top of your tax obligations and meet the deadlines to avoid any unnecessary penalties.