Set up Apple Pay on Apple Watch
Add a card to Apple Watch
Open the Apple Watch app on your iPhone.
Tap My Watch, then tap Wallet & Apple Pay.
If you have cards on your other Apple devices, or cards that you recently removed, tap Add next to a card you want to add, then enter the card’s CVV.
For any other card, tap Add Card, then follow the onscreen instructions.
Your card issuer may require additional steps to verify your identity.
Choose your default card
Open the Apple Watch app on your iPhone.
Tap My Watch, tap Wallet & Apple Pay, tap Default Card, then select the card.
Reorder payment cards
Open the Wallet app 
on your Apple Watch, touch and hold a card, then drag it to a new position.
On a managed Apple Watch, you can touch and drag both payment cards and passes.
Remove a card from Apple Pay
Open the Wallet app
on your Apple Watch.Tap to select a card.
Scroll down, then tap Remove.
You can also open the Apple Watch app on your iPhone, tap My Watch, tap Wallet & Apple Pay, tap the card, then tap Remove This Card.
Find the Device Account Number for a card
When you make a payment with your Apple Watch, the Device Account Number of the card is sent with the payment to the merchant. To find the last four digits of this number, follow these steps:
Open the Wallet app
on your Apple Watch.Tap to select a card, then tap Card Information.
Note: If you select an Apple Card, you must enter your Apple Watch password before you can see the card details.
You can also open the Apple Watch app on your iPhone, tap My Watch, tap Wallet & Apple Pay, then tap the card.
Change your default transaction details
You can change your in-app transaction details—including default card, shipping address, email, and phone number.
Open the Apple Watch app on your iPhone.
Tap My Watch, tap Wallet & Apple Pay, then scroll down to see Transaction Defaults.
Tap an item to edit it.
If your Apple Watch is lost or stolen
If your Apple Watch is lost or stolen, you can:
Put your Apple Watch in lost mode to suspend the ability to pay from your Apple Watch.
Sign in to appleid.apple.com using your Apple ID and remove the ability to pay using your credit and debit cards in Wallet.
In the Devices area, choose the device, then click Remove All under Apple Pay.
Call the issuers of your cards.
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