A Bank Identification Number (BIN) is the leading digits of a payment card number that identify the issuing institution and, indirectly, the card network and product type. Modern BINs are typically six to eight digits (with eight-digit BINs increasingly common under ISO/IEC 7812 updates). Merchants rarely store full BIN tables locally; instead, routing and tokenization services derive scheme and issuer metadata from the BIN at capture time.
BIN drives which network token service applies: Visa BIN ranges route to VTS, Mastercard to MDES, Amex to AETS. Incorrect BIN handling, truncating to six digits when eight are required, or misclassifying a co-badged card, can send provisioning down the wrong path and produce tokens that fail at authorization.
For portability work, BIN also signals whether a stored credential can be network-tokenized at all. Some regional or commercial products have limited token program support; those cards may require PAN fallback in a PCI-controlled vault under the same tok_* reference so your application logic stays uniform.
Veliro uses BIN (and related card metadata from Secure Fields capture) to select the correct scheme enrollment during POST /v1/tokens. Your application keeps one token identifier; the platform resolves scheme-specific provisioning and cryptogram formats behind that reference. Logging BIN alongside tok_* in support tooling helps trace scheme-specific declines without exposing full PAN.