Withdraw $20 from Apple Card

• Do you mean the credit card called Apple Card? If so there is no Cash Advance available on that card.
• If you mean the Apple Cash card, then you can review the Support Article here for how to transfer funds to your bank account or Debit Card. Transfer money in Apple Cash to your bank account or debit card - Apple Support
• If you mean your Apple Account, which may look like a card in your Wallet and labeled  Account, you cannot withdraw cash from that. It is only for purchases to Apple either through an in-app purchase, at apple.com, or in a physical Apple Store.
• If you mean an Apple Gift Card, those are redeemed to your Apple Account and like the above are used for Apple purchases. Gift Cards are not refundable or able to be cashed out in most regions.

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