Microsoft 365 Copilot Expands to Shared and Delegated Mailboxes in Outlook

Access to shared and delegated mailboxes is coming to Microsoft 365 Copilot enabling licensed users to gain greater value from Outlook data through Copilot chat scenarios.

This will be a valuable addition and fills a gap in Copilot's capabilities for many users with responsibilities for monitoring or using mailboxes outside of their own.

Email content continues to be one of the most important Copilot grounding sources for many work processes, so it is encouraging to see this change which will support how more people actually work day-to-day without having to step outside the flow of work.

As always, Copilot will follow existing permissions, so this change only impacts those who have access to or subsequently gain access to a shared or delegated mailbox.

First posted on Linkedin on 10/08/2025 -> View Linkedin post here