Check how to register for Self Assessment

Register for Self Assessment if you’re self-employed

You’ll need to register for both:

Self Assessment
Class 2 National Insurance

Register online

To register, you’ll need to sign into your business tax account and select ‘Add a tax to your account to get online access to a tax, duty or scheme’.

If you do not already have sign in details, you’ll be able to create them when you sign in for the first time.

When to register

You must tell HMRC by 5 October if you need to send a tax return and you have not sent one before. You could be fined if you do not.

If you cannot register online

You can use form CWF1 to register for Self Assessment and Class 2 National Insurance.

The address to send the form to is:

Self Assessment
HM Revenue and Customs
BX9 1AN
United Kingdom

You’ll need to have all your information ready as you cannot save a partly completed form.

What happens next

You’ll usually get your Unique Taxpayer Reference (UTR) by post in 15 working days (21 days if you’re abroad), but it may take longer during busy periods.

You’ll get it sooner in your HMRC app.

If you have not received your UTR within 15 (or 21 days), you can check when to expect it.

You can also find a UTR number if you’ve lost it.

HMRC will contact you by email or post telling you to complete a Self Assessment tax return before it’s due.

You can estimate your Self Assessment tax bill to work out how much tax you are likely to pay.