Hi @Jhon Fredy ,
Based on what I learned about Exchange, there's no limits for the number of mailboxes. And the maximum size of database could be 16TB.
You can only manually decide how many mailboxes & the size of these mailboxes per database.
About the database size: Exchange database size recommendations
Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.
And Best practices for supported storage configurations
Regards,
Lou
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