Register if you’re self-employed
If you have to send a tax return and did not send one last year, you need to register for Self Assessment and Class 2 National Insurance.
Register by 5 October in your business’s second tax year. You could be fined if you do not.
If you’ve sent a return online before
Re-register online (form CWF1).
You’ll need your 10-digit Unique Taxpayer Reference (UTR) from when you registered before. You can find your UTR if you do not know it.
If you have not sent a return online before
Register online. When you register, HM Revenue and Customs (HMRC) will:
- send you a letter with your 10-digit Unique Taxpayer Reference (UTR)
- set up your account for the Self Assessment online service
If you already have a UTR (for example, if you’ve sent a paper return before or registered by phone), create an account for the online service instead.
What happens next
You’ll get a letter within 10 working days (21 days if you’re abroad) with an activation code for your online account. You’ll need this the first time you sign in. You can get a new activation code if you do not receive it or you lose it.
Other ways to register
You can fill this form on-screen then print off and post to HMRC. You’ll need to have all your information ready as you cannot save a partly completed form.
Source: HMRC