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Top domain mail flow report in Exchange Online is retiring

Plan for Change
Major Change

Message ID

MC1272554
View in Admin Center

Services

Exchange Online

Summary

The Top domain mail flow report in Exchange Online's Exchange admin center will retire on July 6, 2026. After this, it will be inaccessible, requiring admins to adopt alternative reporting methods. No other mail flow reports or mail delivery behaviors are affected. Prepare by updating documentation and validating new workflows.

Details

Introduction

We’re retiring the Top domain mail flow report in the Exchange admin center (EAC) in WW. This change is part of our ongoing work to streamline and modernize mail flow reporting in Exchange Online, helping admins consolidate workflows and adopt more flexible reporting options.

When this will happen

The Top domain mail flow report will be retired on July 6, 2026.

How this affects your organization

Who is affected

  • Admins who use the Top domain mail flow report in the Exchange admin center (EAC) in WW. 

What will happen

  • The Top domain mail flow report will no longer be accessible in EAC after July 6, 2026.
  • Any workflows that rely on this report for troubleshooting, monitoring, or reporting will need to transition to an alternative reporting method.
  • No other Exchange Online mail flow reports are impacted by this change.
  • This retirement does not change mail delivery behavior or message routing.

What you can do to prepare

  • Update internal documentation, runbooks, and bookmarks that reference the Top domain mail flow report.
  • Capture any baseline metrics you need before July 6, 2026.
  • Validate an alternative workflow for identifying top sender and recipient domains.
  • Review Exchange Online reporting options to ensure your organization has the tools needed to support ongoing mail flow analysis.

Compliance considerations

No compliance considerations identified. Review as appropriate for your organization.

Timeline

Published
Apr 6, 2026
Message published to Message Center
Updated
Apr 6, 2026
Message content updated
Action Required By
Jul 5, 2026
Action deadline
End Date
Aug 31, 2026
Message timeline ends

Tags

#User impact#Admin impact#Retirement

Category

Plan for Change

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