Because the cash transfer of CCB credit card will charge interest in addition to the handling fee, and the way to charge interest is to charge interest from the date of entry (0.05% interest per day) and compound interest on a monthly basis. So if you have money, you'd better pay it back as soon as possible, so the interest will be less.
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Precautions for the use of bank cards:
When the cardholder spends more than the amount approved by the issuing bank, he will no longer enjoy the interest-free period and pay overdraft interest from the date of overdraft.
When users enjoy interest-free repayment of credit cards, remember not to exceed the credit limit approved by the bank, otherwise they will not be able to enjoy interest-free repayment and pay interest on the overdraft limit.
During the interest-free repayment period, full repayment does not require interest. But for partial repayment, there are two ways to calculate interest within the minimum repayment amount stipulated by the bank. The first way is that as long as the cardholder doesn't pay back a penny within the repayment period, he can't enjoy interest-free treatment, and the other way is to pay only the interest on the arrears.
Baidu Encyclopedia-CCB Credit Card