File your tax return online
You can use the online service to:
- fill in and send your tax return to HM Revenue and Customs (HMRC)
- go back to a tax return you’ve already started
- check your details, view returns and print your tax calculation
You’ll need to register for Self Assessment again if you’ve sent a tax return in the past but you did not have to send one last year.
This page is also available in Welsh (Cymraeg).
If you’re filing online for the first time
You must have received your Unique Taxpayer Reference (UTR), enrolled for the online service and activated your account using the code you received in the post.
How you do those things depends on whether you’re:
Sign in to file your tax return
You’ll need to prove your identity using Government Gateway or GOV.UK Verify.
If you have not told HMRC you need to send a return
There are different ways to register for Self Assessment if you’re:
You should allow enough time to complete the registration process so you can send your return by the deadline.