Microsoft Outlook: Copilot account switcher in the Outlook side pane

Introduction Microsoft is introducing a Copilot account switcher in the Copilot side pane in the new Outlook for Windows. The account switcher shows the active Copilot‑enabled account and allows users to change the Copilot account used in the side pane in supported experiences. This message is associated with Microsoft 365 Roadmap ID 559991. When this will happen Targeted Release: Rollout will begin in late April 2026 and is expected to complete by mid-May 2026. General Availability (Worldwide): Rollout will begin in mid-May 2026 and is expected to complete by mid-June 2026. How this affects your organization Who is affected Users in Microsoft 365 tenants using the new Outlook for Windows Only users with multiple Copilot-enabled accounts configured in Outlook What will happen Users will see a new account selector at the top of the Copilot side pane in supported experiences. The selector shows the currently active Copilot-enabled account. The account selector appears only when multiple Copilot-enabled accounts are available and the account context may be ambiguous (for example, certain Calendar experiences). Users will be able to switch Copilot accounts within the Copilot side pane without changing Outlook’s broader account context. If you are using Mail, you will not see the Copilot account switcher.  There is no impact for users with a single Copilot-enabled account. The feature is enabled by default and respects existing Copilot availability and licensing. The Copilot account switcher is available to users with Microsoft 365 Copilot (Premium) and Copilot Chat (Basic). This is a multi-account feature and requires at least two Copilot-enabled accounts, in any combination of Premium and/or Basic. What you can do to prepare No action is required. To prepare for user questions, we recommend that administrators: Update internal documentation for Copilot usage in multi-account scenarios. Inform users who work across multiple accounts how to confirm or change the active Copilot account in the Copilot side pane. Update helpdesk guidance for users who have multiple Outlook accounts configured. Compliance considerations No compliance considerations identified. Review as appropriate for your organization.