How to transfer Apple Account balance to Apple Card

Sorry, but Apple Account balance can not be transferred back to your banking account, unless required by law.

You will have to spend the money buying content from Apple or ask Apple to clear the balance.

Contact Apple Support - Apple Support

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If cash refunds are required by law

You can’t redeem or return Apple Gift Cards, App Store Gift Cards, or unused Apple Account balance for cash, except as required by law. If your jurisdiction allows for refund of redeemed gift balances, you can contact Apple Support to request a refund. When you contact Apple, include the primary email address that you use to sign in to your Apple Account.

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copied from: Change your Apple Account country or region - Apple Support

Please contact Apple Support immediately and request a reverse transfer. Apple will be able to transfer back to the original source of the transfer only. There can be time limitations.

 Please call  1-800-MY-APPLE, or review you options provided in the link below.

https://support.apple.com/en-us/HT201232