The $100 already showing in the Microsoft account means the two $50 gift cards were successfully redeemed. For Microsoft and Xbox gift cards, once redeemed there is no separate “code” to use at checkout; the money sits as an account balance and is spent directly from the Microsoft account.
To use this balance for subscriptions or other purchases at Microsoft Store (online, Windows, or Xbox):
- Sign in with the same Microsoft account that shows the $100 balance.
- Go to the Microsoft Store or the subscription purchase page (for example, Microsoft 365) and start the purchase.
- At checkout, choose the Microsoft account balance as the payment method. If the full subscription price is covered, it will be paid entirely from that balance; if not, another payment method can be added for the remainder.
Key points from the terms:
- A Microsoft account is required to redeem and use gift cards.
- When a gift card is redeemed, its full value is added to the Microsoft account balance; it is not re‑issued as another code.
- Non‑promotional account balance does not expire, so the $100 balance itself will not expire.
- If the account balance is insufficient for a purchase, another payment method must be used for the remaining amount.
If the wrong type of code was redeemed (for example, a Microsoft 365/Office product key instead of a currency gift card), that must be redeemed in the correct place (such as Office.com/setup for Microsoft 365/Office product keys, or the Windows Activation settings for Windows product keys), but standard Microsoft currency gift cards always convert into account balance and are then used directly at checkout.
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