The available credit line of ICBC refers to the credit card overdraft limit. ICBC Credit Card is a credit card product handled by ICBC for users, which can realize the functions of cash withdrawal, cash deposit and withdrawal, credit card overdraft, shopping installment payment and so on.

When the available balance is zero, the credit line has all been used up, and no overdraft is allowed. When the available balance is negative, it indicates that the credit card has a registered but unpaid debt. When the balance is positive, it means that the card has a balance in addition to the repayment bill, which is also called overpayment.