Understanding Self Assessment and your tax return

You must send your Self Assessment tax return and pay any tax you owe to HM Revenue & Customs (HMRC) on time. There are a number of deadlines for Self Assessment that you must keep in mind.

Self Assessment deadlines

• Register for Self Assessment by 5 October 2020
• Paper tax returns midnight 31 October 2020
• Online tax returns midnight 31 January 2021 (you can submit your return up to 28 February 2021 without getting a late filing penalty - see Self Assessment deadline reminder)
• Pay the tax you owe midnight 31 January 2021 (if you pay your tax or set up a payment plan by 1 April 2021 you will not be charged the initial 5% late payment penalty - more help for Self Assessment taxpayers)

If you fail to meet the deadline you may have to pay a penalty.

When the deadline is different

Submit your online return by 30 December if you want HMRC to automatically collect tax you owe from your wages and pension. You must be eligible.

HMRC must receive a paper tax return by 31 January if you're a trustee of a registered pension scheme or a non-resident company. You can't send a return online.