Microsoft wants to help prevent spam by placing greater limits on the number of emails an Exchange Online account can send per day.

Starting in January 2025, Microsoft is introducing a limit on the number of emails you can send in Exchange Online. The email limit for bulk email sending is 2,000 external recipients per day. Microsoft introduces the so-called External recipient tariff (ERR) to prevent misuse of Exchange Online. The regular recipient rate limit, which also applies to internal emails, remains at 10,000.

Microsoft will roll out the new ERR to new Exchange Online tenants starting January 1, 2025. The limit will then be extended to the remaining Exchange Online customers between July and December 2025.

Fight against spam

With the limitation, Microsoft hopes to continue the fight against spam. An attacker who compromises a mailbox also has his limits. Of course, there are also legitimate reasons to exceed the ERR limit, but these will no longer be supported by Exchange Online from 2025.

If you want to reach more than 2,000 external recipients per 24 hours, you can use other services such as Azure Communications Services for email. Microsoft notes that, unlike Exchange, this solution is designed to send large volumes of email to recipients outside of your tenant.