CVV2 Location on VISA, MC and DISCOVER CREDIT CARDS:

The CVV2 three-digit value is printed on the signature panel on the back of Visa, Mastercard and Discover cards immediately following the credit card number.

CVV on Visa card

CID Number Location on AMERICAN EXPRESS cards:

The Card Identification Number is the 4 digit, non-embossed number printed above your credit card number on the face of your card. This number is recorded as an additional security precaution.

CVV on AMEX cards