Can I leave my Steam or Xbox game library to someone when I die?

No — on both platforms, what you have is a personal, non-transferable license, not property, and both companies' own agreements say so directly.

Valve's Steam Subscriber Agreement states: "Subscriptions are not transferable, and even if your access to a Subscription for a particular game or application is terminated, the original activation key will not be able to be registered to any other account, even if the Subscription was obtained in a retail store." The same agreement lets you cancel your own account at any time, but explicitly warns that doing so "will not entitle you to any refund." Source

Microsoft's rules for Xbox and other digital purchases are just as direct: "Except as may be permitted below, you may not transfer or resell any licenses to any Digital Goods," and if you sell a device that has digital content on it, "the purchaser will not acquire any right to use the Digital Goods." Source

In practice, this means a game library — however large or expensive — isn't something a will can leave to anyone, because there's no ownership to transfer in the first place; the license was personal to the account, and ends with it (or simply sits inaccessible if no one ever closes the account). The one narrow workaround Microsoft documents elsewhere is Xbox's "Home Xbox" console sharing feature, which lets a second person play games tied to your account from a shared console — but that's account access continuing to work because credentials or a linked device are shared, not a transfer of ownership the license itself recognizes.

What we could not verify: PlayStation's equivalent terms — this pass checked Steam and Microsoft only; do not assume PlayStation's policy is identical without checking Sony's own agreement directly.

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