Understanding Self Assessment and your tax return

Self Assessment tax return deadlines


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.

The last tax year started on 6 April 2020 and ended on 5 April 2021.

Self Assessment deadlines

There is usually a second payment deadline of 31 July if you make advance payments towards your bill, know as payments on account.

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.

HMRC might also email or write to you giving you a different deadline.

Partnership returns if you have a company as a partner

If your partnership’s accounting date is between 1 February and 5 April and one of your partners is a limited company, the deadline for:

  • online returns is 12 months from the accounting date
  • paper returns is 9 months from the accounting date

2019 to 2020 tax year and earlier

The Self Assessment deadline for these tax years has passed. Send your tax return or payment as soon as possible - you’ll have to pay a penalty.