This post has been republished via RSS; it originally appeared at: New blog articles in Microsoft Community Hub.
Today, we are announcing that, beginning in January 2025, Exchange Online will begin enforcing an external recipient rate limit of 2,000 recipients in 24 hours.
Exchange Online does not support bulk or high-volume transactional email. We have not enforced limiting of bulk email until now, but we plan on doing so with the introduction of an External Recipient Rate (ERR) limit. The ERR limit is being introduced to help reduce unfair usage and abuse of Exchange Online resources.
What about the Recipient Rate Limit?
Exchange Online enforces a Recipient Rate limit of 10,000 recipients. The 2,000 ERR limit will become a sub-limit within this 10,000 Recipient Rate limit. There is no change to the Recipient Rate limit. If you send to less than 2,000 external recipients in a 24 hour period, you will still be able to send to 10,000 total recipients.
How will this change happen?
The new ERR limit will be introduced in 2 phases:
- Phase 1 - Starting Jan 1, 2025, the limit will apply to cloud-hosted mailboxes of all newly created tenants.
- Phase 2 - Between July and December 2025, we will start applying the limit to cloud-hosted mailboxes of existing tenants.
What are the options for customers who have business needs that exceed the ERR limit?
If you have a cloud-hosted mailbox that needs to exceed the ERR limit, you can move to Azure Communication Services for Email, which is designed specifically for high volume email sent to recipients external to your tenant.
Exchange Online Transport Team