Self assessment deadlines for 2026 to 2027

Self assessment always looks back. You earn income during a tax year that runs from 6 April to 5 April, and you report it afterwards. LITRG, the Low Incomes Tax Reform Group, summarises the usual pattern: a paper return is normally due by 31 October after the end of the tax year, and an online return must usually be submitted on or before 31 January following the end of the tax year. Your balancing payment of tax is due on that same 31 January.

The dates below for 2026 to 2027 are worked out by applying that usual pattern, because GOV.UK's deadlines page currently shows only the dates for the 2025 to 2026 return. HMRC has not yet published them as 2026 to 2027 dates, so check GOV.UK before you rely on one.

One thing that catches people out is that two of these payments are made before the year has been reported at all. Payments on account are advance payments based on last year's bill, so the first one towards 2026 to 2027 is due in January 2027, while the tax year is still running.

While 2026 to 2027 is still running, the deadlines most people are working towards belong to the 2025 to 2026 return. GOV.UK states that the online return must be submitted by 11:59pm on 31 January 2027, and that the tax must be paid by the same time. If you want your bill collected through your tax code instead of paid in one go, you must submit by 11:59pm on 30 December 2026. The paper deadline of 31 October 2026 has already passed, and the registration date of 5 October 2026 has too.

If you make payments on account, the 31 January 2027 payment usually also includes the first payment towards 2026 to 2027, with the second following by 31 July 2027. Our guide to payments on account explains who has to make them and how they are worked out.

Missing the registration date does not leave you without a deadline. GOV.UK says that if you register after 5 October 2026, HMRC will send you a letter or email with a different deadline to send your tax return by, and this will be 3 months from the date on the letter or email. The payment date does not change, so the tax you owe is still due by 11:59pm on 31 January 2027.

Telling HMRC late can also lead to a penalty for failing to notify, which GOV.UK says is based on the amount still left to pay. LITRG notes that if you notify late but pay your tax in full by 31 January, HMRC should reduce that penalty to zero. Our guide on how to register for self assessment covers the steps.

If you are within Making Tax Digital for Income Tax, quarterly updates sit on top of the annual timetable. HMRC lists 7 August 2026, 7 November 2026, 7 February 2027 and 7 May 2027 as the four quarterly update deadlines for 2026 to 2027, with the tax return submitted straight from compatible software by 31 January 2028. Making Tax Digital applies from 6 April 2026 to people with qualifying income of more than £50,000 from self-employment and property, falling to more than £30,000 from April 2027 and more than £20,000 from April 2028. HMRC has said there are no penalties for missing a quarterly update deadline for the 2026 to 2027 tax year.

This guide is general information, not tax advice, and your own dates can differ, for example if you registered late or HMRC has written to you with a different deadline. If you would rather someone else kept track of the calendar, our self assessment tax returns page explains what that involves. We read every enquiry and, where we can, we will put you in touch with a local accountant, though we cannot promise one will be available. You can get in touch at any time of year.