Format: nLength: 3Fixed length
DE 51
Currency Code, Cardholder Billing
What it is
ISO 4217 code of the cardholder billing currency (pairs with DE 6).
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.