Exchange Online limits
This is the maximum number of recipients that a user or mailbox can send to in a 24-hour period. These limits are applied per user to all outbound and internal messages.
Related Topics:
Number User Distribution Boxes
Creating and modifying a distribution group in Office 365
If you or someone in your organisation sends email to a lot of users at once, you can send to a distribution group so you don''t exceed the maximum number of recipients per message.
How to count distribution list members in Outlook?
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
Is there a limit on number of members you can have in a group
For your question "Is there a limit on number of members you can have in a group/distribution list ?" YES, the maximum number of distribution group members are 100,000
Distribution groups
Microsoft 365 Groups are similar to distribution groups in that they allow you to communicate with multiple people in one email message, and they also come with a shared mailbox, calendar,
Distribution lists in Office 365
In this case, each plan allows one user to create up to 250 instead of 300,000 distribution lists. A complete summary of distribution list limits is available here.
Article
The maximum number of recipients allowed in the To:, Cc:, and Bcc: fields for a single email message is set per user at 500 recipients. This can be increased by the admin to up to 1,000.
About shared mailboxes in Microsoft 365
Too many users: A shared mailbox supports a maximum of 25 users. If too many users access the mailbox at the same time, they might experience connection failures or duplicated
Distribution lists in Office 365
In this case, each plan allows one user to create up to 250 instead
Manage distribution groups in Exchange Server, Exchange distribution
Mail-enabled universal distribution groups (also called distribution groups) can be used only to distribute messages. Mail-enabled universal security groups (also called security groups) can
Distribution group Exchange on-premises vs Exchange Online is there
The only difference is if you have Exchange Online as a standalone option. In this case, each plan allows one user to create up to 250 instead of 300,000 distribution groups.