1. Bank of China website or mobile banking inquiry: log in to Bank of China official website or mobile banking, enter the "Inquiry" column, select "My Account" or "My Card", and select the business travel card to inquire about the balance.
2. Bank of China self-service terminal inquiry: Go to the Bank of China self-service terminal, select "Inquiry Balance", and enter the business travel card number and password to inquire the balance of the business travel card.
3. Inquire at the counter of China Bank: Go to the counter of China Bank, show your valid certificate and tell the teller that you need to inquire the card number and password of the business travel card balance, and the teller will help you to inquire and inform the balance.