Office 365 mail sending limits

Adrian Date 6 Reputation points
2021-02-07T00:08:03.637+00:00

I understand that Office 365 has a max of 30 emails sent per minute. If I send 40 in a minute, what happens to the extra 10 emails ? Are they held and sent next minute time frame or are they just lost ?

Exchange Server Management
Exchange Server Management
Exchange Server: A family of Microsoft client/server messaging and collaboration software.Management: The act or process of organizing, handling, directing or controlling something.
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  1. Andy David - MVP 142.7K Reputation points MVP
    2021-02-07T00:16:45.303+00:00

    If you are referring to the SMTP client sending limits ( does not apply to Outlook Web Access or Outlook in "Exchange" mode), then if that limit is exceeded, the messages over the limit are rejected:

    Message rate limit: Message rate limits determine how many messages a user can send from their Exchange Online account within a specified period of time. This limit helps prevent over consumption of system resources by a single sender. If a user submits messages at a rate that exceeds the limit via SMTP client submission, the messages will be rejected and the client will need to retry.

    https://learn.microsoft.com/en-us/office365/servicedescriptions/exchange-online-service-description/exchange-online-limits#sending-limits-1

    2 people found this answer helpful.