Card PIN management is the set of processes by which a card issuer handles the personal identification number attached to each card. It covers creating or choosing the PIN, delivering it securely, checking it at each use, changing it, and unblocking it after too many wrong attempts.
The PIN is never stored or transmitted in readable form. It is encrypted at the keypad into a PIN block, and all generation and verification take place inside a hardware security module, under the PCI PIN Security requirements. Issuers once posted PINs in sealed mailers; most now reveal them in a mobile app or let customers set them there or at an ATM. With an EMV chip card the PIN can be checked online by the issuer or offline by the chip; an offline PIN is changed or unblocked by an issuer script sent to the chip. Fintech programmes obtain these functions from their issuer processor.