Deadlines
Compare paper, online and registration dates.
Self Assessment deadlineUK tax tools · source checked
Your Self Assessment filing route.
Applicable tax year: 2026/27Last checked:
Which tax year is this filing season for?
The current tax year runs from 6 April 2026 to 5 April 2027. The standard online deadline in January 2027 relates to the earlier year, from 6 April 2025 to 5 April 2026. Select that completed year when checking a return due this winter.
| Action | 2025/26 return | 2026/27 return |
|---|---|---|
| Tell HMRC a return is needed | 5 October 2026 | 5 October 2027 |
| Paper return received by HMRC | 31 October 2026 | 31 October 2027 |
| Online return and balancing payment | 31 January 2027 | 31 January 2028 |
| Online filing for collection through a tax code | 30 December 2026 | 30 December 2027 |
| Second payment on account, if required | 31 July 2027 | 31 July 2028 |
Dates for 2026/27 follow the annual deadline rules; an HMRC notice can set a different filing date. Check the deadline rules and exceptions. The deadline for payment is separate from an extended filing deadline.
Where do I start?
Do I need to file a Self Assessment? Work through that decision before registering. The next pages answer a specific question:
Registration
Find the right registration route and how to obtain a UTR.
Register for Self AssessmentPenalties
Separate late filing charges from late payment charges.
Self Assessment penaltyHMRC Self Assessment help: fix common errors covers access, missing details and amendments.
What happens if a return or payment is late?
A late return can start with a £100 charge, even if no tax is due, with later charges as the delay increases. After 3 months, daily charges are £10, capped at £900. After 6 months and again after 12 months, the additional standard charge is 5% of tax due or £300, whichever is higher. Late payment has separate percentage charges and interest. Read the penalty rules; see the full penalty table.