The interest of ICBC's credit card is calculated according to the outstanding balance of each settlement period, instead of adding the outstanding interest to the principal of the next settlement period. Specifically, the interest calculation of ICBC credit cards usually follows the following steps:

1, settlement cycle: credit cards generally take a month's settlement cycle, for example, from 1 to the last day of the month.

2. Unpaid balance: At the end of each settlement cycle, if the cardholder has unpaid balance, that is, it exceeds the minimum repayment amount of the credit card, this unpaid balance will be included in the next settlement cycle.

3. Interest is calculated according to the outstanding balance of each settlement period. ICBC credit cards generally use the daily interest method, that is, the annual interest rate is divided by 365 days, and then multiplied by the outstanding balance and the number of days in the settlement period to get the interest amount in the settlement period.