Register for Self Assessment
You must register for Self Assessment if you have to send a tax return.
You’ll need to register again if you did not send a tax return last year, even if you’ve sent one in the past.
This guide is also available in Welsh (Cymraeg).
How to register
There are different ways to register if you’re:
When to register
You must register for Self Assessment by 5 October. You could be fined if you do not.
Once you’ve registered, you can send your tax return online any time before the deadline.