Members of my family plan cannot use copilot

This behavior is intentional.

For Microsoft 365 Family subscriptions, all family members can use the Microsoft 365 apps, but AI features like Copilot (including Copilot in Word, Excel, PowerPoint, Outlook, Designer, and OneDrive) are only available to the subscription owner. These Copilot/AI benefits cannot be shared with other members of the family group.

If other family members want Copilot access, they need their own eligible subscription such as Microsoft 365 Personal or Microsoft 365 Premium.

References:

• Frequently asked questions about Copilot in OneDrive
• Learn more about sharing your Microsoft 365 Family or Premium subscription
• Sharing Copilot in Outlook
• The Microsoft 365 app transition to the Microsoft 365 Copilot app