Understanding Self Assessment and your tax return
Self Assessment is a system HM Revenue & Customs (HMRC) uses to collect Income Tax. Income Tax is usually deducted automatically from wages, pensions and savings. However, people and businesses with other income must report it in a Self Assessment tax return.
Do I need to file a Self Assessment tax return?
You can find out who must send a tax return and check if you need to fill in a Self Assessment return.
Self Assessment deadline
The deadline to submit your Self Assessment tax return and pay the tax you owe is midnight on 31 January 2021 (you can submit your return up to 28 February 2021 without getting a late filing penalty).
This guide will help you understand Self Assessment including how to register for Self Assessment with HMRC, how to file your first Self Assessment tax return and key deadlines for Self Assessment.