Different Qualifiers in X12 Reference Identification (REF) Segment

The REF (Reference Identification) segment in X12 EDI transactions is used to specify reference information, such as codes, numbers, or identifiers that provide additional context to a transaction. 

Each qualifier in the REF01 element indicates the type of reference being provided.

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Common Qualifiers in the REF Segment

Qualifier (REF01)	Description
PO	Purchase Order Number
IA	Internal Vendor Number
DP	Department Number
CR	Customer Reference Number
CO	Customer Order Number
SI	Shipper’s Identifying Number for Shipment
IN	Invoice Number
PK	Packing List Number
BT	Batch Number
IT	Internal Customer Number
QN	Purchase Order Change Number
ZZ	Mutually Defined Reference Identifier
BM	Bill of Lading Number
CN	Carrier’s Reference Number (PRO/Tracking Number)
E9	Department of Transportation (DOT) Hazardous Certificate Number
ST	Store Number
VC	Vendor Contract Number
PG	Product Group
TN	Transaction Reference Number
18	Plan Number
19	Division Identifier
BL	Government Bill of Lading
LU	Location Number
MC	Motor Carrier Number
SC	Shipper’s Car Order Number
AG	Agent's Shipment Number
DO	Delivery Order Number
RZ	Returned Goods Authorization Number

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REF Segment Structure

The REF segment includes three data elements:

• REF01: Reference Identification Qualifier (e.g., PO, SI).
• REF02: Reference Identification (actual value associated with the qualifier, e.g., 12345 for a Purchase Order Number).
• REF03: Optional Description (additional context for the reference).

Example:

REF*PO*123456789~

REF*BM*PRO123456~

REF*VC*Contract56789~

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X12 - REF Segment Key Points

1. Context-Sensitive: The meaning of a qualifier depends on the EDI transaction set (e.g., 850, 856, 810). For example:
• PO in an 850 refers to the Purchase Order Number.
• BM in an 856 refers to the Bill of Lading Number.
2. Mandatory or Optional: Some REF segments are mandatory depending on the business use case and EDI standards.
3. Custom Qualifiers: ZZ can be used for mutually defined codes that are agreed upon between trading partners.