Microsoft Excel: Enabling M365 subscribers to use Copilot Chat in locally stored modern workbooks

We’re enabling Microsoft 365 subscribers to use Copilot Chat when working in Microsoft Excel modern workbooks (.xlsx, .xlsb, .xlsm, .ods, .xltx, .xltm, and .xlam files) stored locally. This brings parity with workbooks stored in SharePoint or OneDrive, allowing users to query Copilot Chat regardless of storage location.

When this will happen

General Availability (Worldwide): Rollout will begin in mid-December 2025 and is expected to complete in January 2026.

How this affects your organization:

Who is affected: All Microsoft 365 subscribers using Excel modern workbooks stored locally.

What will happen:

• Microsoft 365 subscribers will be able to query Copilot Chat when opening and working in locally stored Excel modern workbooks.
• This feature is enabled by default; no admin action is required.
• There is no impact to existing workflows for workbooks stored in SharePoint or OneDrive.

What you can do to prepare

All locally stored Modern Excel workbooks are blocked today from querying Copilot Chat. We are enabling M365 subscribers who open these workbooks and query Copilot Chat. See Manage Microsoft 365 Copilot Chat to manage that chat experience.

Learn more:

• Manage Microsoft 365 Copilot Chat | Microsoft Learn
• Overview of Microsoft 365 Copilot Chat | Microsoft Learn

Compliance considerations

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