For a Microsoft 365 Family subscription, the subscription holder and everyone it is shared with can install the Microsoft 365 desktop apps on all their devices, but only five devices can be signed in at the same time per account.
To understand where the licenses (installs/sign-ins) are used, check from the subscription holder’s account:
- Sign in with the subscription holder’s Microsoft account at the Microsoft 365 services page (Services & subscriptions).
- From there, manage the Microsoft 365 Family subscription sharing and see who it has been shared with.
- Each person the subscription is shared with can install the apps on their own devices and sign in on up to five devices at the same time. If more than five devices are used, the oldest signed‑in device is signed out automatically.
If a device is unexpectedly signed out, simply sign back in on that device to continue using Microsoft 365. For more details on how sign-in limits work and how to manage devices and installations, see the guidance under “Manage your Microsoft 365 devices and installations” and “How sign in works in Microsoft 365.”
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