Credit cards usually have three kinds of interest rates. First, credit cards can be overdrawn, and the current rates are 0.6% and 0.55%. Second, when the amount is high, the bank will recommend the cash installment business, which will involve the monthly interest rate of cash installment, which is about 0.6%-0.8%. Third, the cash withdrawal business, you can directly take a credit card to the ATM to withdraw cash, the interest is five ten thousandths.

On the surface, these three rates seem low, but if you are good at calculation, you will find that they are quite different. The first kind of overdraft consumption is credit card consumption. The current interest rates are 0.6% and 0.55%; The second kind of gold installment business is also one of the main businesses promoted by the bank's credit card department, and the cash installment interest rate given by banks is around 0.7%. The third type is credit card ATM cash withdrawal. Every bank's credit card has this service, and the rate is five ten thousandths. At present, many platforms engaged in micro-credit loans generally adopt this interest rate.

If the rate of consumer credit card is 0.6% and the average service life is 50 days, the annualized conversion rate is 0.6%/50x365 = 4.38%; The general cash installment business rate is 0.7%, and the service life is calculated as one month: the annualized conversion rate is 0.7% *12 = 8.4%; Credit card cash withdrawal business, the rate is 0.5 ‰ per day, and the term is one day: the annualized conversion rate is 5/10000 * 30 *12 =18%. At present, the annualized rate of return of one-year time deposit in the bank is 1.5%, which means that if the income of the deposit bank cannot cover the overdraft of your credit card.