HMRC urges people to start Self Assessment early ahead of 31 January 2027 deadline

HM Revenue and Customs (HMRC) published an appeal on 10 November 2026 urging Self Assessment customers not to wait until the last minute to complete their tax return.

Deadline and scale of the issue

The online return for the 2025/26 tax year must be filed, and any tax paid, by 31 January 2027. HMRC estimates that around 12 million people file a return each year, of whom around 5 million usually leave it until January.

According to an HMRC-commissioned survey of more than 5,200 people, 35% said they are confident they stay on top of their financial admin. More than 18% said they put it off before a deadline because they lack confidence, and nearly a quarter said they put it off because it feels overwhelming. More than half of respondents named GOV.UK as their go-to source of help with tax matters.

Myrtle Lloyd, HMRC's Chief Customer Officer, said there is still plenty of time, and that starting early allows people to check their return thoroughly and spot any mistakes.

Filing early does not mean paying early

People who file now do not have to pay straight away. They have time to plan for any tax owed before the deadline. The quickest way to pay is through the HMRC app, which can also help people find their UTR, view previous tax summaries and payment history, and set payment reminders.

People with PAYE income who file online before 30 December may in some cases have tax owed collected through their tax code.

Other things to know

• Anyone unsure whether they need to file a return can use the checker tool on GOV.UK. People can also register for Self Assessment online, or tell HMRC they no longer need to file a return.
• Customers signed up to Making Tax Digital for Income Tax still submit their 2025/26 return in the usual way and pay any tax owed by 31 January 2027.
• Those who received the 2025 Winter Fuel Payment and are in Self Assessment will see it pre-populated in their return where possible; if it is not shown, it must be added manually. People with total income over £35,000 will pay it back through their tax bill.
• Child Benefit details are now pre-populated for people who pay the High Income Child Benefit Charge through Self Assessment. Some people may be able to pay the charge monthly through their tax code.
• Cryptoasset gains above the £3,000 annual tax-free allowance for Capital Gains Tax must be declared in the 2025/26 return.

What this means for you

This applies to people living in the UK who are self-employed, have additional income or are subject to the charges described above, if they need to file a Self Assessment return. It is worth checking on GOV.UK and, if needed, registering or using HMRC's support materials, including webinars and YouTube videos.