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.
Register by 5 October in your business’s second tax year. You could be fined if you do not.
If you have not filed a tax return before
- 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.
- 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.
- 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.
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.
If you’ve filed a tax return before but you did not use the online service
Sign in to your business tax account and add Self Assessment. You’ll need your Government Gateway user ID and password to sign in.
You can create a business tax account if you do not have one. Set up an account as an organisation, not as an individual.
You’ll need your 10-digit Unique Taxpayer Reference (UTR) from when you first registered for Self Assessment to file a return. 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.
Register by post
Register for Self Assessment and Class 2 National Insurance by filling in a form on-screen then printing it off and posting it to HMRC. You’ll need to have all your information ready as you cannot save a partly completed form.
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After you’ve registered, you’ll receive a letter with your Unique Taxpayer Reference (UTR) number within 10 working days (21 if you’re abroad).
You’ll receive a reminder letter telling you to complete a Self Assessment tax return before it’s due.
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
- 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).
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.
You must also register your partnership if you’re the ‘nominated partner’.
There are different ways to register:
- for limited liability partnerships
- if you’re a partner that’s not an individual, for example a company or a trust