The credit card PIN is a security code used by credit cards when conducting online or telephone transactions. On the back of a bank credit card, there are 7 digits (also 8 digits) in boldface. The first four digits are the last digits of the bank card number, and the three digits after the space character are the pin code.

The credit card pin code is a code introduced to improve the payment security of credit cards and prevent the leakage of credit card information. The pin code stands for personal identification number (pin=personal identification number), a secret identification code used to protect smart cards from misuse.

The credit card pin code is different from the transaction password and withdrawal password, and the three are independent of each other. In China, credit cards usually do not have a PIN code. In this case, the PIN code is the last three or four digits of the credit card signature. If the user sets a credit card password, the pin code is the credit card password. Credit card pin codes are commonly used abroad.