The method of distinguishing the main card and the supplementary card of a credit card (credit card) is as follows: judge by the limit, the main card has a high limit, the supplementary card has a low limit; judge by the annual fee, the supplementary card's annual fee The fee is only half of that of the main card; judging by management rights, the main card has higher rights. The main card can cancel the supplementary card and take back the limit of the supplementary card; judging by the application conditions, you must have the main card before you can apply for the supplementary card.

Therefore, users can choose the above methods to distinguish the main card and the secondary card of a credit card (credit card), but the two cards are actually independent of each other in terms of usage rights.