according to the law, it is legal to use someone else's credit card with the explicit consent of the credit card holder. Credit card holders can choose to authorize others to use their own credit cards. In this case, users can legally use credit cards for transactions. However, this authorization should be clear, and it is best to record it in writing or other provable ways to ensure that the rights and interests of both parties are protected. Therefore, it is very important to ensure the clear consent of the cardholder before using other people's credit cards.