Security

Microsoft Abandons Plan to Restrict Bulk Email Sending on Exchange Online

Published

3 months ago

January 6, 2026

Microsoft Cancels Exchange Online Bulk Email Sending Limits

Microsoft made a significant decision to revoke the previously announced daily limit of 2,000 external recipients on Exchange Online bulk email senders. This change comes after negative customer feedback and operational challenges reported by users.

The initial announcement regarding the implementation of new External Recipient Rate (ERR) limits was made in April 2024, with plans to enforce the limit between July and December 2025. The purpose of these limits was to combat spam and prevent abuse of Exchange Online resources by Microsoft 365 customers.

However, in response to customer concerns, Microsoft decided to indefinitely cancel the Exchange Online bulk emailing rate limit. The Exchange Team acknowledged the feedback and expressed a commitment to finding solutions that balance security and usability without causing disruptions.

While the cancellation of the bulk emailing rate limit is a positive development for users, Exchange Online still maintains other limits. These include a Recipient Rate limit of 10,000 recipients and a Tenant External Recipient Rate Limit of 5,000 external recipients per day.

In a similar move, Google has also strengthened its defenses against spam and phishing attacks by blocking emails from bulk senders who do not meet stricter spam thresholds. Google’s guidelines mandate email authentication through SPF/DKIM and DMARC for domains sending more than 5,000 messages per day to Gmail accounts.

To comply with Google’s guidelines, bulk email senders must avoid sending unsolicited messages, provide an easy unsubscribe option, and promptly respond to unsubscribe requests. Failure to adhere to these guidelines may result in Gmail rejecting all offending emails.

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