Primary Account Number (PAN)
What it is
The cardholder account number as embossed / encoded on the card — up to 19 digits, LLVAR.
The PAN identifies the card: the first 6–8 digits are the BIN/IIN that routes the transaction to the issuer, the last digit is the Luhn check digit. In authorization messages it arrives from the terminal (keyed, swiped, dipped, or tapped); in tokenized transactions the DPAN travels here instead of the real PAN.
PCI DSS treats DE 2 as cardholder data: it must be masked when displayed (at most the BIN and last 4 digits) and rendered unreadable in storage. DE 34 (PAN, extended) exists for account numbers that do not fit DE 2 conventions and is rarely used.
Example values
16 4761739001010119LL=16 length prefix followed by a 16-digit Visa test PAN.Specification reference
Defined in ISO 8583:1987 (base). Card networks publish their own dialect tables (Visa BASE I / V.I.P., Mastercard CIS) that refine formats, lengths, and — for private-use elements — the entire layout. Always confirm against the interface specification you implement.