Table of Contents
What are the current Exchange Online bulk email limits after the recent policy reversal?
Microsoft has officially abandoned the “Mailbox External Recipient Rate Limit” (ERRL) policy originally scheduled for implementation in April 2026. This decision follows significant feedback from system administrators regarding the limitations of current bulk email options. While this specific restriction is cancelled, organizations must strictly adhere to existing sending limits to maintain tenant health.
The Cancelled Policy Explained
The Exchange Team previously proposed a strict cap on outbound communications. The plan detailed in the April 2025 TechCommunity announcement aimed to limit Exchange Online mailboxes to 2,000 external recipients per 24 hours.
Microsoft designed this restriction to curb spam and prevent abuse of their infrastructure. The policy targeted April 2026 for enforcement. However, this hard limit would have severely impacted legitimate organizations that rely on Exchange Online for high-volume operational workflows.
Why Microsoft Reversed the Decision
The reversal stems directly from customer impact analysis. Following the initial announcement, administrators made it clear that a 2,000-recipient cap would disrupt critical business processes.
Specifically, Line-of-Business (LOB) applications often utilize Exchange Online to send invoices, statements, and notifications. Because alternative bulk shipping options currently lack the necessary capabilities to handle these workflows seamlessly, Microsoft acknowledged that enforcing the limit would cause operational failures for many tenants. Consequently, the Exchange Team updated their stance in January 2025 to cancel the rollout indefinitely.
Current Sending Limits and Compliance
With the cancellation of the ERRL, the standard Exchange Online limits remain in effect. Administrators should configure their environments based on the following established thresholds:
- Recipient Rate Limit: 10,000 recipients per day.
- External Recipient Limit: 5,000 external recipients per day (varies by subscription but generally serves as the standard active limit).
Note: These limits apply to individual mailboxes. They are not intended to support mass marketing campaigns.
Strategic Recommendations for Admins
Although Microsoft halted this specific restriction, they remain committed to eliminating spam. Do not interpret this cancellation as permission to abuse the service.
- Segregate Traffic: Differentiate between transactional email (invoices, password resets) and marketing email.
- Evaluate Alternatives: Investigate Microsoft’s High Volume Email (HVE) preview or third-party SMTP services (such as SendGrid or Azure Communication Services) for applications exceeding 5,000 daily external recipients.
- Monitor Usage: Regularly audit mailbox statistics. If Microsoft detects abuse from LOB applications, they may still restrict individual tenants to protect the wider network IP reputation.
The April 2026 deadline for the 2,000 external recipient limit is no longer a concern. However, relying on Exchange Online for bulk sending remains a risky long-term strategy. You should plan for dedicated bulk emailing infrastructure to ensure future deliverability and compliance.