HM Revenue & Customs

What details do I need to register (sign up) for the Self Assessment online service?


To register (sign up) as an Individual, you need to enter your Unique Taxpayer Reference (UTR), and either your National Insurance Number or your postcode. You can now also select 'living abroad' if this is appropriate .

You'll find your UTR on your Self Assessment tax return, a Notice to complete a Tax Return or on your Statement of Account. It may also be on other documents. Or you can contact your local tax office.

Trusts and Partnerships

To register (sign up) as either a Trust or Partnership, the Trustee or 'nominated partner' must enter the Trust or Partnership Unique Taxpayer Reference (UTR) and postcode.


To register (sign up) as an Agent, you must enter your Self Assessment Agent Reference Number and your postcode. Contact your local tax office if you don't have a Self Assessment Agent Reference Number.