Glossary
Issuer
The bank or institution that issued the customer's card or account and decides whether to approve each transaction.
The issuer holds the cardholder relationship, extends the credit or holds the funds, and makes the authorization decision. Decline reasons — insufficient funds, suspected fraud, expired card, issuer unavailable — originate here.
Because acceptance rates vary significantly by issuer and geography, issuer behaviour is one of the strongest inputs into routing and retry strategy.