An issuer identification number (IIN), sometimes referred to as a bank identification number (BIN), is the first 6 to 8 digits of a payment card account number. It identifies the issuing bank, card type, and country of origin. IINs are used for routing, fraud detection, and analytics. Card networks maintain global IIN databases, which are frequently updated.
Reviewing IIN data helps identify high-risk issuers or trends in authorization declines. AltoPay uses this information in fraud rules, velocity checks, and chargeback management to prevent abuse. If you notice chargebacks tied to specific IINs or regions, this data can inform your transaction screening strategy. Filtering or limiting risky IINs is a preventive step many high-volume merchants adopt.
For more than a decade, Jessica Velasco has been a thought leader in the payments industry. She aims to provide readers with valuable, easy-to-understand resources.
