Hi,@Ella Taylor
Thanks for posting your question in the Microsoft Q&A forum.
Based on your description, I ran the same test and did get the same results as you described.
This happens because, behind the scenes, the distribution group is expanded to its individual members by the Exchange server before the email is sent out. Therefore, the server logs the email as being sent to each individual email address rather than the distribution group as a whole.
I've noticed that when using Message trace, the results returned are not only messages sent to members but also to groups.
Since the status sent to the group is 'Expanded', we can filter based on the status sent.
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