Update 9/17/2025: Updated GCC dates.
As with all cloud services, Exchange Online imposes service limits to prevent misuse of Exchange Online resources and ensure availability for all users. For exa...
Updated Sep 30, 2025
Version 21.0
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Works for me and my customers. Just checked the #Messages in some customer tenants using the "outbound TLS Report" at https://admin.cloud.microsoft/exchange#/reports/outboundconnectordetails. It's is not 100% accurate for that but if a german production 10.000 Seats Tenant may send 324k Mails in 24h and is currently using 40k/day peak, then we are far away from these limit. I think thousands others are safe, too.
Bit i have told them every time, that Exchange online is for "humans" not for Listservers, massmailers, ERP-Relays etc. they should have a look at other options. (Azure Communication, Sendgrid, Mailchimp, Mailgun and many others. and implement SPF, DKIM ,DMARC for besser deliverey rates at all
KevinShaughnessy
Microsoft
MicrosoftFrank Carius Thanks for sharing that. Indeed there are multiple ways to assess current volume without the dedicated report available quite yet. The cmdlet noted in the FAQ above is probably the most accurate for the current 24-hour volume and threshold: Get-LimitsEnforcementStatus. Check the Threshold and ObservedValue properties.
Only a super small % of legitimate tenants will be impacted by this, and those that are, are egregiously blasting out bulk mail (or potentially are compromised). As more admins determine their threshold versus actual volume (via the cmdlet or after the report goes live this week) the vast majority will see they're also well under quota and won't be impacted by this.