Option 1, Address Verification: enter in the numeric portion of the street address, zip code, and VISA card number and it will advise you if there is a match.
Option 2, Issuing Bank Phone numbers: enter the VISA card number and it will provide you with the 800 number for the issuing bank if available.
You will need your Discover Merchant number. Enter the Discover card number and address information, and it will advise you if there is a match.