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X12 271 response guide

Interchanges, groups, and transactions

X12 documentation uses envelope for the header-and-trailer pairs that delimit parts of a message. An interchange contains functional groups, and each group contains transaction sets.

Interchange: ISA and IEA

Section titled “Interchange: ISA and IEA”

ISA starts the interchange, and IEA ends it. This pair comes from the single-benefit response:

ISA*00*          *00*          *ZZ*CEDARVALLEYHP  *ZZ*OAKSTMEDGROUP  *990101*1201*^*00501*000000101*0*P*:~
...
IEA*1*000000101~
  • ISA01 through ISA04 show that the example does not supply authorization or security information. The blank fields retain their fixed widths.
  • ISA05/ISA06 identify the sender, and ISA07/ISA08 identify the receiver. Both use the mutually defined ZZ qualifier.
  • ISA09 and ISA10 carry the interchange date and time. ISA11, ISA12, and ISA16 establish the repetition separator, control version, and component separator.
  • ISA13 is the interchange control number. The same value appears in IEA02.
  • IEA01=1 reports one functional group in this interchange.

See the public ISA and IEA field references.

Functional group: GS and GE

Section titled “Functional group: GS and GE”

GS and GE surround a functional group:

GS*HB*CEDARVALLEYHP*OAKSTMEDGROUP*20990101*1201*101*X*005010X279A1~
...
GE*1*101~
  • GS01=HB identifies the functional group as eligibility, coverage, or benefit information.
  • GS02 and GS03 carry the application sender and receiver codes.
  • GS04 and GS05 carry the group date and time.
  • GS06=101 is the group control number. It matches GE02.
  • GS07=X identifies X12 as the responsible agency, while GS08=005010X279A1 identifies the implementation convention used here.
  • GE01=1 reports one transaction set in the group.

See the public GS and GE field references.

Transaction set: ST and SE

Section titled “Transaction set: ST and SE”

ST and SE surround one business transaction:

ST*271*0101*005010X279A1~
...
SE*10*0101~
  • ST01=271 identifies an eligibility, coverage, or benefit response.
  • ST02=0101 is the transaction control number. It matches SE02.
  • ST03=005010X279A1 identifies the implementation convention used by the transaction.
  • SE01=10 counts every segment from ST through SE, including both.

See the public ST and SE field references.

These pairs close in reverse order: ST/SE, then GS/GE, then ISA/IEA. A file can contain more than one interchange, as shown by X12 RFI 1585. Each route can set its own file and batching rules.