YES, the maximum number of distribution group members are 100,000 members. You can refer to Exchange Online limits - Service Descriptions | Microsoft LearnThe limits in Microsoft Exchange Online fit into one of the following categories: The limits applied to a Microsoft 365 organization may differ depending on how long the organization has been enrolled in the service. Number of groups created by a single user/admin:. Managing contact groups in Outlook can sometimes be challenging, especially when you need to know the number of members in a distribution list. Outlook doesn't offer a built-in feature for this, leaving many users unsure of how to quickly get an accurate count. This service is fully integrated with Azure Active Directory (AAD). For active employees. The primary purpose of a distribution list is to send emails to multiple recipients – yes, as simple as that.
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