How to Access the Self Assessment Gateway
The HMRC Self Assessment Gateway is accessed at gov.uk/log-in-file-self-assessment-tax-return. You log in using your Government Gateway user ID and password. If you do not have a Government Gateway account, you can create one during the registration process โ you will need your National Insurance number and either a valid UK passport or a recent P60 to verify your identity.
Retrieving a Forgotten UTR
Your Unique Taxpayer Reference (UTR) is a 10-digit number found on correspondence from HMRC โ Self Assessment notices, tax calculations or welcome letters. If you cannot find it: log into your Personal Tax Account at gov.uk, or call HMRC's Self Assessment helpline (0300 200 3310). UTRs cannot be retrieved online instantaneously โ HMRC may need to post it to your registered address, which takes up to 10 working days.
Logging In: Personal Tax Account vs Self Assessment
HMRC has two main online portals: the Personal Tax Account (for viewing your tax record, checking NI contributions, updating address) and the Self Assessment return (for filing your annual return). Both are accessed through the Government Gateway with the same login. The Self Assessment section is accessed via 'Self Assessment' in the menu once logged in.
What to Do If Locked Out
If you have forgotten your Government Gateway user ID or password, use HMRC's online recovery process. You will need your NI number and one of: P60, payslip, or valid UK passport. The recovery process typically generates a new user ID sent to your registered email. If you cannot recover access online, call HMRC directly โ waiting times can be long so email contact may be faster for non-urgent issues.