Email send limit exceeds for tenant need email alerts before reach the limit

Yes. Email alerts are available for outbound sending limits.

For the tenant external recipient limit, the built-in alert policy Email sending limit exceeded can notify the TenantAdmins group by email. The alert policies are enabled by default and can be reviewed or modified in the Microsoft Defender portal on the Alert policy page.

A practical setup is:

1. Open the Microsoft Defender portal.
2. Go to Alert policy.
3. Find Email sending limit exceeded.
4. Review or modify the notification settings so the required admins receive the email alerts.

To monitor how close the tenant is to the Tenant External Recipient Rate Limit (TERRL), use:

• Exchange admin center > Reports > Mail flow
• Tenant Outbound External Recipients report

That report shows TERRL usage for the organization.

If alerts are needed before the limit is reached, Microsoft recommends creating a custom alert policy, for example at 80% of TERRL, so there is time to redistribute sending or move bulk/high-volume external email to another service.

For bulk or high-volume external email, the recommended alternative is Azure Communication Services email.

• Troubleshoot outbound sending limits and blocked users in Exchange Online
• Troubleshoot outbound sending limits and blocked users in Exchange Online
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