ISO 8583 DE Reference
Format: anLength: 12Fixed length
DE 37

Retrieval Reference Number (RRN)

Data element
37
Format
an
Length
12
Encoding type
fixed
Bitmap
Primary

What it is

The RRN is the human-visible transaction reference: it is printed on receipts, quoted in disputes, and used to retrieve the original transaction in chargeback processing. A common (not mandated) composition is YDDDHHNNNNNN — Julian date and time plus the STAN.

Example values

621414320512Composed from Julian date 6214, hour 14, and STAN 320512.

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.

Decode & build this element

📅Julian Date Converter📦ISO 8583 Parser

Related data elements

DE 11System Trace Audit Number (STAN)DE 7Transmission Date & Time
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