At a meeting of the Virtual Communications Group on 21 March 2016 HMRC explained the forthcoming changes to logging in for HMRC online services.
Until 31 May, customers can still access HMRC services using the existing HMRC Government Gateway login page. After 31 May access to this page will be removed. Agents and their clients who have bookmarked this page will then have to use the new HMRC Government Gateway login page to access online services. Users will be automatically re-directed to the new login page if they try to access the old login page.
Software developers have been informed of this change and have been requested to update their software packages with access links to the new HMRC Government Login page by 31 May.
Some agents and their clients may use 'silent login' - their own background login mechanisms that they have developed to log into the HMRC website (with Government Gateway Usernames and Passwords). In this case those users may also need to update the links to HMRC login pages within their internal systems. Note that existing submissions to the Government Gateway API (Submission Protocol) will not be affected by this change.