How to register for Self Assessment. If you need to file a Self Assessment tax return and you have not previously registered for tax and you also need to pay your Income Tax liability (both of which should be done by 31 January), you need to register for Self Assessment and obtain your own Unique Tax Reference code (UTR).

This is a freeview 'At a glance' guide to registering for Self Assessment.

At a glance

You are self-employed, you have started working for yourself, see our guide: Self Employment: Registering for Tax.

If you have other income or capital gains to report and are not Self Employed, the registration process is as follows:

  1. Go to (this takes you to HMRC's sign-up pages.
  2. Click on ‘not self-employed’, It will take you to the next page:
  3. Click on ‘Register for Self Assessment using form SA1’.
  4. Click on the first option given (the online version of form SA1). You are now taken to the Government Gateway.
  5. If you have not already got an account, go to ‘Create sign-in details’. You will then be asked for your email address and sent a code.

The sign-up will continue once you verify the code.

Have a pen handy as it will give you an account number and you need to note down your password.

The security questions take some time to go through and they will require you to upload various items to prove your ID. Normally this will be things like a copy of your passport and verifying figures on employee annual payslips.

Once registered, it takes about 10 days for HMRC to issue you with a UTR.

When do I have to pay tax?

  • Tax is paid on 31 January following the end of the last tax year, with an interim payment made by the following 31 July.
  • The actual amounts due will depend on your profit levels. 
  • If HMRC does not issue you with a Unique Taxpayer Reference in time to pay your tax liability, you can still make a payment using your National Insurance number. This may prevent Late payment penalties and interest from being charged. 


Be very careful about being caught by phishing (fake) websites that pretend to be HMRC.

HMRC will never charge you to register for tax, file a tax return or claim a tax refund or overpayment.

HMRC will never send you an email to say that you have a tax refund.

You can find details of tax refunds and tax due on your Business Tax Account, once it is set up.

HMRC's confirmed URL for registration is


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