Office 365 email sending limits

Please, note! You can only send from one email address unless your device can store login credentials for multiple Microsoft 365 or Office 365 mailboxes. Office 365 also has a cap of 500 separate recipients for each individual mail, as well as a cap of 30 outgoing messages per minute.
 
To help stay below the usage limit, place frequent mail recipients into a static or dynamic distribution group. Messages sent to distribution groups only count as a single email, regardless of how many members the group has. If you need to send out frequent bulk messages to a variety of people, but want to keep your existing mail system for regular emailing, you can subscribe to an external bulk mail service to send messages on your behalf.