Generally, it is the most cost-effective to swipe the CCB credit card one day after the bill date, and you can enjoy the longest interest-free period. Because the bill has been issued, when swiping the card the next day after the bill is issued, the consumption account counts the time when the bill comes out next month. At this time, it will be nearly a month before the bill comes out next month. After the bill comes out, there are still 20 days before the repayment date, and you can enjoy an interest-free period of at least 50 days in total. This is the most cost-effective way to swipe your card.