How to register for self assessment

There are different ways to register for self assessment, if you’re self-employed, not self-employed but need to declare income, or if you’re in a business partnership.

Watch this video to find out about how you register for Self Assessment.

HMRC is the UK’s tax, payments and customs authority. HMRC collect the money that pays for the UK’s public services and help families and individuals with targeted financial support.

1. 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 both:

Self Assessment
Class 2 National Insurance

How you register depends on whether you’ve sent a tax return before or not.

If you have not filed a tax return before:

1) Register for Self Assessment and Class 2 National Insurance through your business tax account. You’ll need a Government Gateway user ID and password to sign in. If you do not have a user ID for a business tax account, you’ll be able to create one.

2) You’ll receive a letter with your Unique Taxpayer Reference (UTR) number within 10 days (21 if you’re abroad). You’ll need your UTR to file a return.

3) You’ll receive a reminder letter or email telling you to complete a Self Assessment tax return before it’s due.

If you’ve filed a tax return online before:

Re-register online (form CWF1) for Self Assessment and Class 2 National Insurance if you’ve filed a return before, but did not file one last year.

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.

You’ll receive a reminder letter or email telling you to complete a Self Assessment tax return before it’s due.

You can file your tax return any time before the deadline.

2. Register if you’re not self-employed:

If you have to send a tax return and did not send one last year, you need to register for Self Assessment by 5 October. If you have not filed online before, register for Self Assessment using form SA1. You can either register online or fill in, print out and post the form

After you’ve registered, you’ll receive your Unique Taxpayer Reference (UTR) number in the post within 10 working days (21 if you’re abroad).

If you registered online, once you’ve received your Unique Taxpayer Reference (UTR), sign in to your personal tax account to activate your Self Assessment.

3. Register if you're a partner or partnership

You must register for Self Assessment by 5 October if you’re a partner in a partnership.

You’ll need your partnership’s 10-digit Unique Taxpayer Reference (UTR). You can find a UTR if you’ve lost it.