Which payment method is charged for purchases that family members make?
When Purchase Sharing is turned on, everyone's purchases bill to the family organizer's payment method.* If there's an issue with the payment method, the family organizer can update their payment method or add a new one.
If you're the family organizer and you don't want to share a payment method with your family, turn off purchase sharing. When purchase sharing is turned off, you can continue to share subscriptions like Apple TV+ and Apple Arcade. When Purchase Sharing is turned off, everyone must use their own payment method.
* Learn how purchases are billed if a family member has Apple ID balance.