HMRC: 100 days left to file 2025-26 Self Assessment

HMRC has confirmed the online Self Assessment deadline for the 2025 to 2026 tax year is 31 January 2027. The paper filing deadline is earlier, 31 October 2026. HMRC expects around 12 million people to file a return by the January deadline.

Anyone new to Self Assessment needs to register first to get a Unique Taxpayer Reference (UTR), which is required before you can file. HMRC says filing early lets you find out what you owe sooner, budget for the payment, and get any refund faster.

HMRC also flags two items that may appear pre-filled on returns this year: the 2025 Winter Fuel Payment (or Pension Age Winter Heating Payment in Scotland) for customers in Self Assessment, and Child Benefit details for those who pay the High Income Child Benefit Charge through Self Assessment. On the Winter Fuel Payment, HMRC says customers should check it is shown and add it manually if it is not. Paper filers need to add it themselves.

HMRC separately reminds anyone who sold cryptoassets that gains above the tax-free allowance need to be declared on the 2025 to 2026 return.

This applies to landlords in England, Wales, Scotland and Northern Ireland who report rental income through Self Assessment. The filing and payment deadline is the same across the UK.

If you are signed up to Making Tax Digital for Income Tax, HMRC says you still need to file a Self Assessment return and pay by 31 January 2027 in the usual way.

• Check whether you need to register for a UTR if this is your first Self Assessment return
• Gather your rental income and expenses for the 2025 to 2026 tax year
• File online by 31 January 2027, or by 31 October 2026 if filing on paper
• If you received the 2025 Winter Fuel Payment, check whether it is shown on your return and add it manually if it is not
• If you sold cryptoassets, check whether you need to declare a gain
• Check with an accountant if you're unsure what counts as income or an allowable expense, or whether MTD for Income Tax applies to you