File your Self Assessment tax return and pay your tax bill by 31 January 2026

Are you prepared for the online Self Assessment tax return and payment deadline of midnight on Saturday 31 January 2026?

HM Revenue & Customs (HMRC) is encouraging its Self Assessment customers to prepare and file their tax return before the 31 January 2026 deadline.

The deadline to file your Self Assessment tax return online and pay the tax you owe for the 2024 to 2025 tax year is 11:59pm on Saturday 31 January 2026.

The benefit of filing early

HMRC is encouraging customers to complete their Self Assessment tax return as soon as they can, so they know what they owe and can budget to make the payment by 31 January 2026. This also means that if a repayment is due, it can be claimed back sooner.

Do I need to file a Self Assessment tax return?

HMRC customers who are unsure if they need to file a tax return can check if they need to send a Self Assessment tax return.

New to Self Assessment

Anyone who is new to Self Assessment needs to register for Self Assessment to receive their Unique Taxpayer Reference before they can send a tax return for the 2024 to 2025 tax year.

No longer need to file a tax return?

People who no longer need to file a tax return should tell HMRC as soon as possible to avoid any penalties.

Paying your Self Assessment tax bill

Find out the various payment options to help you pay your Self Assessment tax bill.

Penalties

Reasons for not paying your tax bill or arranging a payment plan by the deadline will be considered individually by HMRC. While people who provide HMRC with a reasonable excuse may avoid a penalty, those without a reasonable excuse will be issued with a penalty, including:

• an initial £100 fixed penalty, which applies even if there is no tax to pay, or if the tax due is paid on time
• after 3 months, additional daily penalties of £10 per day, up to a maximum of £900
• after 6 months, a further penalty of 5% of the tax due or £300, whichever is greater
• after 12 months, another 5% or £300 charge, whichever is greater

There are also additional penalties for paying late of 5% of the tax unpaid at 30 days, 6 months, and 12 months. If tax remains unpaid after the deadline, interest will also be charged on the amount owed, in addition to the penalties above.

Self Assessment help webinars

HMRC is hosting a number of live webinars focusing on a range of Self Assessment topics in January. These webinars are free and last around one hour.

Register for the latest HMRC tax webinars.

Additional Self Assessent help

HMRC has also produced a series of  YouTube videos to help people complete their return. You can also access help online with Self Assessment

First published 6 January 2026