Mailbox usage reports

Use the mailbox usage reports to get information about users with a mailbox and their level of activity which is primarily based on emails sent and received. You can also see how much storage each mailbox consumes and how many mailboxes are approaching storage quotas.

Note: For details about different report views and names, see Office 365 Reports - Mailbox usage.

Reports

Function Return Type Description
Get mailbox detail Stream Get details about mailbox usage.
Get mailbox counts Stream Get the total number of user mailboxes in your organization and how many are active each day of the reporting period. A mailbox is considered active if the user sent or read any email.
Get quota status mailbox counts Stream Get the count of user mailboxes in each quota category.
Get storage Stream Get the amount of storage used in your organization.