Credit cards are generally repaid before the end of the last repayment date. The bank will send you a bill every month. The deadline for credit card transactions recorded on the bill is the billing date, and the repayment date is generally around 18 after the billing date. Three days after the date of repayment is the grace period for repayment. So just pay it back before the repayment date. If you don't pay back after the repayment date, there is still a grace period of three days, but if you don't pay back after the grace period, the bank will count you as overdue, and then you will have to pay liquidated damages and overdue penalty interest.