Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
A single Microsoft account can have only one active Microsoft 365 subscription at a time, so the two Microsoft 365 Family memberships cannot be “combined” into one bigger plan. What can be done is to stack the time of multiple Family subscriptions on the same Microsoft account.
When a new Microsoft 365 Family subscription is added to an account that already has an active Microsoft 365 Family subscription, the remaining time on the existing subscription is extended by the duration of the new one. For example, if there are 6 months left on the current Family subscription and a new 12‑month Family subscription is redeemed on the same Microsoft account, the result is 18 months of Microsoft 365 Family on that account. This stacking can be done up to a maximum of 5 years of prepaid time; attempting to exceed that will cause a Redemption Failed error.
To use the bundle purchase, redeem the new Microsoft 365 Family product key or offer on the same Microsoft account that already holds the active Family subscription. The benefits (number of users, devices, storage, etc.) will stay the same; only the expiration date will move further into the future.
If the second Family subscription was purchased under a different Microsoft account, it cannot be merged across accounts. In that case, either:
- Redeem the new key on the account that already has Family (if it has not yet been redeemed elsewhere), or
- Let one subscription expire and then continue with the other account going forward.
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