Hi Adrien
Welcome to MS Q&A
EntraID licensing is indeed based on human identities rather than individual user accounts. The goal is to ensure that each human identity that interacts with Microsoft 365 services is properly licensed for features like Privileged Identity Management (PIM) and Conditional Access.
In your scenario, where you have 100 users but half of them have two accounts each (one for operations and one privileged), you would need to license based on the total number of human identities.
So, if you have 100 users and each user corresponds to one human identity, you would need to purchase licenses for those 100 human identities, regardless of the number of accounts each user has.
Therefore, you would need 100 EntraID P1 or P2 licenses for PIM and Conditional Access, depending on the features and capabilities you require. There's no need to purchase licenses for the total number of accounts (150 in your case), as the licensing is based on the number of distinct human identities.
Please check Imag for ref
Please check this doc for detailed info https://learn.microsoft.com/en-us/entra/id-governance/licensing-fundamentals
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