The Microsoft 365 subscription is tied to the Microsoft account used to buy/redeem it, not to the physical computer. It does not need to be “canceled on the old computer” to use it on the new one.
Use these steps on the new Dell:
- Go to https://www.office.com.
- Sign in with the same Microsoft account that was used when the subscription was set up on the HP.
- Select Apps (or go to the Install apps option).
- Choose Install apps to download the installer.
- Run the downloaded file and complete the installation; the desktop Office apps will activate against the existing subscription.
If the subscription was purchased as a separate Microsoft 365 product (not bundled through a third-party store subscription like Apple/Google), it can be installed on the new device this way without canceling or buying again.
If the subscription itself was purchased through a third-party retailer with its own recurring billing (for example, via an app store), subscription management and cancellation must be done with that retailer, but the Microsoft 365 apps can still be installed on any supported device by signing in with the same Microsoft account.
If the goal instead is to stop being billed for this personal subscription because another subscription (for example, from a school or work account) is now available, cancel it as follows:
- Go to https://account.microsoft.com/services.
- Sign in with the same Microsoft account used to purchase the subscription.
- Under Services & subscriptions, find the Microsoft 365 subscription.
- Select Manage.
- Select Cancel subscription (or Upgrade or Cancel) and follow the prompts.
- If Turn on recurring billing is shown instead of Manage or Cancel, the subscription is already set to expire on the date shown and will not be charged again.
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