Register for Self Assessment

Business: Business Tax

    Once you’’ve registered for Self Assessment with HM Revenue and Customs (HMRC), you’’ll get a Unique Taxpayer Reference (UTR) number and you can then send your tax return to HMRC.

    Before you register

    You’’ll need your:

    • National Insurance number
    • personal contact details – eg address
    • business details – eg business address, date you started self-employment or joined a partnership

    You must be the ‘nominated partner’ (the partner responsible for sending in the partnership tax return) if you’re registering a new business partnership.


    You should register by 5 October following the end of the tax year you need to send a tax return for. This way, you’ll have enough time to complete registration before the tax return and any tax is due. You may have to pay a penalty if you register late.

    How to register

    How you register depends on your circumstances.

    Your circumstanceYour reason for registeringHow to register
    New sole traderYou’ve not registered beforeSole trader – register for Self Assessment
    Existing sole traderYou’ve registered before and need to re-register (eg you’re starting self-employment again)Existing sole trader – register for Self Assessment
    PartnershipsYou’re the nominated partner and you need to register both yourself and the business partnershipPartnership – register for Self Assessment using form SA400
    Partner non-individualYou’re registering a partner that’s joining a business partnership and they’re not an individual (eg a company or trust)Partner non-individual – register for Self Assessment
    Any other reasonEg you or your partner get Child Benefit and your income is over £50,000, you owe tax from investment profits etcRegister for Self Assessment using form SA1

    How to get an online account

    You need an HMRC online account (also known as a ‘Government Gateway’ account) to send a tax return online.

    New sole traders and business partnerships can register for Self Assessment and get an online account at the same time.

    If you’re not one of these groups, you have to sign up for an online account after you’ve registered for Self Assessment.

    It takes 7 working days to set up an online account because HMRC posts you an ‘activation code’ – you need this to ‘activate’ your account. It can take up to 21 days if you’’re abroad.

    Register for Self Assessment – forms including SA1, SA400, SA401, deadlines and your Unique Taxpayer Reference (UTR) number