Update 7/14/2025: Updated the FAQ.
As with all cloud services, Exchange Online imposes service limits to prevent misuse of Exchange Online resources and ensure availability for all users. For examp...
Updated Jul 14, 2025
Version 18.0
Blog Post
As an ISV based around the Power Platform / D365 CE with north of 100 customers, this new enforcement is less than ideal (putting it politely) - the extremely short notice for the implementation (especially given that no reports are available in EAC at present), compounds the issue further as we are faced with a situation of having to abandon our roadmap to develop a solution to use a different mail solution (I find myself leaning towards a solution that does NOT factor any Microsoft technology, which feels wrong given our Cloud Solution Partner designation).
Are there any allowances or considerations being given to customers that use the Server-Side Sync features within your other product offerings such as Power Platform / Dynamics 365? The reason for asking this is because the other limit that was being imposed (https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-introduce-external-recipient-rate-limit/4114733) specifically states that that limit is NOT being applied to Server-Side Sync.
KevinShaughnessy
Microsoft
MicrosoftRichLiddington2 yes, these will get counted as part of the TERRL as server-side sync scenario sends messages out from the tenant in which the sync'd mailbox exists, and it's the tenant sending that's being tracked here.
Thanks for clarification KevinShaughnessy - although I would like to understand why there is a different approach between MERRL and TERRL, as it is making no sense to me whatsoever. MERRL will give (when new limits imposed) up to 2k external recipients, but TERRL is going to drastically reduce that number if you are an Enterprise customer?
I am fully expecting escalations from a number of our key customers ... multi-million $ arrangements with MS including Azure, Surface, Power Platform, Dynamics F+O, etc... and this limit is being enforced at next to no notice, which is highly likely to impact their business.
Please see my comment at Introducing Exchange Online Tenant Outbound Email Limits | Microsoft Community Hub