The final repayment date of CCB's credit card is the 20th day after the billing date, and your credit card billing date is the 7th of each month (fixed), so the final repayment date is the 20th day after the billing date, that is, the 27th of each month.

July 8-August 7 is a billing cycle. Credit card consumption in this cycle will generate a bill on August 7, and August 27 is the final repayment date. Full repayment before this date is interest-free.

August 8-September 7 is a billing cycle, and the credit card consumption in this cycle will generate a bill on September 7, and September 27 is the final repayment date. Full repayment before this date is interest-free. And so on.

Therefore, if the bill is swiped on the same day, the interest-free period is the shortest, only 20 days (swiping the card on August 7 and repaying it on August 27). If you swipe your card after the bill, the interest-free period is the longest, 50 days (swipe your card on August 8 and repay it on September 27). Be sure to know the billing date and repayment date of your credit card so as not to miss it.