Back in April 2024, Microsoft announced that it would be imposing External Recipient Rate (ERR) limits of 2,000 emails per user/mailbox over a 24-hour rolling window in Exchange Online. Initially, it stated that it would make this configuration change from January 2026, but it later pushed this date forward to April 2026 for new and trial tenants, and October 2026 for existing tenants. Now, it has finally decided to cancel this modification.
For those unaware, Exchange Online has a recipient rate limit of 10,000 emails within a 24-hour window. Microsoft says that while Exchange Online is not designed for bulk transactional email, it has not enforced this limit. It changed its tune in April 2024 when it noted that it would impose a limit of 2,000 emails for external recipients and that limit would be a subset of the overall limit of 10,000 emails. What this meant was that if you have a sales team that regularly shoots out marketing emails to potential customers, they would only be able to send 2,000 emails per user/mailbox within a 24-hour window.
However, it appears that this configuration change was not very popular among customers and Microsoft has decided to cancel it indefinitely. Exchange Online users had filed complaints explaining that this limit would introduce significant hurdles in daily operations, and that other bulk email alternatives do not suit their needs. As such, Microsoft has listened to customer feedback and not implemented these limits.
It is important to note that Microsoft"s recipient rate limit is still in place, and this announcement just impacts the ERR limit. The Redmond tech giant has further emphasized that despite this cancelation, its goals remain the same. It will continue to fight against the abuse of Exchange Online resources for sending spam and performing other malicious activities. As such, it has hinted at working on other implementations that achieve these goals with "less" disruptions to businesses.