The so-called interest-free period refers to the buffer period for customers to save money after the credit card balance is zero (or the balance in the card is less than the commodity price), which generally means that customers will have this interest-free period after spending. The longest interest-free period, as an explanation, if the bank stipulates the 25th of next month as the repayment period, then the longest interest-free repayment period is 56 days if you spend 1 this month. Consume on the 2nd of this month, and the repayment period is 55 days. At present, the longest interest-free period is 56 days for Bank of Communications, Industrial and Commercial Bank of China and Agricultural Bank of China.