Your mother dies on Monday, but her credit card is still sitting in your wallet because she made you an authorized user years ago. On Tuesday, you use it to buy groceries for the house, fill her car with gas, or pay for flowers for the funeral, figuring you’ll sort everything out when the estate is settled. That can create a problem because permission to use someone’s credit account while they’re alive shouldn’t be treated as permission to keep borrowing through that account after their death. The rules surrounding a credit card after death also depend on whether you’re merely an authorized user, a true joint account holder, or someone with legal authority over the estate. Before making another purchase, here’s what families need to understand.