Microsoft Cancels Exchange Mailbox External Recipient Rate Limit

After considering customer feedback, Microsoft cancelled the mailbox external recipient rate limit for Exchange Online. The idea behind the new limit was simple – it makes life more difficult for spammers to use Exchange Online as a platform. Unhappily, customers didn’t like losing the ability to send relatively small amounts of external email for different reasons, and Microsoft didn't have a cost-free alternative to offer. C’est la vie.

https://office365itpros.com/2026/01/08/mailbox-external-recipient-rate/