1 May 2025 marks the end of sale for new customers of Azure AD External Identities Plan 2 and Azure AD B2C – Microsoft Entra External ID is Microsoft’s latest Customer Identity and Access Management (CIAM) solution for managing identity, authentication and authorisation of external users.

This site gives information about required actions for existing customers of the older solutions (https://bit.ly/42E3i1d), and there’s a useful FAQ here: https://bit.ly/4jNr2Yl.