Introducing Exchange Online Tenant Outbound Email Limits

Hi Again

I am trying to reply to Nino's comment in my previous comment, but the Reply link is not working.

Nino, thanks for replying but I need a little more clarification:

"Both MERRL and TERRL will exist as their own separate limits. One is on the mailbox and one on tenant level"

Does this means that the two limits are cumulative, so for instance a single mailbox cannot send more than the 2k daily limit even if the tenant has a 10k (or higher) limit?

In your timeline diagram you show two email messages, the first with 4k recipients and the second with 6k. This implies that the tenant limit applies, but an individual mailbox was able to send more than 2k external messages in a day.

This is an extremely important point for one of my clients, as they have had to move a few mailboxes back to their Exchange Servers to route mail out directly due to exceeding limits. We're planning to disable centralised routing and send all mail from Exchange Server out via their Exchange Online tenant soon, we need the Purview DLP protections so cannot plan to route mail out directly via Exchange Server, and are concerned that we'll hit these limits.

While I (and all of us) appreciate that Exchange Online is not a bulk mail service, understanding the specific limits for those occasional burst mail scenarios is proving very complicated.

Thanks!