Bank cards are divided into credit cards and savings cards. Generally, putting money into your savings card will generate certain interest expenses. If you want to deposit or transfer cash into a credit card, not only will there be no interest charges, but some banks will also incur handling fees. Even if there is no handling fee for saving money, there will be a handling fee for withdrawing money, which is much more than the handling fee, and some of them are even equivalent to the handling fee generated by credit card overdraft.