What does the Build Benefit Enrollment EDI (X12 834) skill do?

Convert member eligibility changes into an ASC X12N 834 Benefit Enrollment and Maintenance transaction (005010X220A1) — sponsor/payer identification, INS maintenance types (add/change/terminate/reinstate) and relationship codes, HD coverage and effective dates, full-file vs change-file handling, and a worked example

How do I run the Build Benefit Enrollment EDI (X12 834) skill?

Copy the skill and paste it into your own Claude or ChatGPT, then provide your source data. FinchContext skills run inside your own AI assistant, so your financial data never leaves your control.

Which region does the Build Benefit Enrollment EDI (X12 834) skill cover?

United States. It targets the local tax authority / e-invoicing format described on this page.

Build Benefit Enrollment EDI (X12 834)

Skill: Convert member enrollment changes into an X12 834 transaction

Region: United States Category: Health Care EDI (HIPAA X12 5010) Does: Takes employer/sponsor member-eligibility data and assembles the ASC X12N 834 Benefit Enrollment and Maintenance EDI transaction — the HIPAA-mandated format a plan sponsor (employer, exchange, or government program) sends to a health plan to add, change, terminate, or reinstate members and their coverage. Spec: ASC X12 005010 — 834 005010X220A1

834 is the enrollment counterpart to the claim/payment transactions; it is governed by its X12 TR3 and frequently constrained by a payer/exchange companion guide (e.g. CMS uses 834 for Marketplace and Medicare enrollment with its own rules). Loop/segment IDs below are the 5010 structure; the TR3 + companion guide are authoritative for usage and code sets.

Transaction envelope

ISA / GS (FG = BE, version 005010X220A1) / ST (834)
  BGN  Beginning Segment   (transaction set purpose: 00 original / 15 reissue, reference, timestamp, action)
  REF  Master policy / transaction set policy number
  DTP  File effective date
  N1   SPONSOR (P5) and PAYER (IN) identification
  ... 2000 member loops ...
SE / GE / IEA

BGN08 action code distinguishes a full file (replace) from a change-only (update) feed — a critical companion-guide setting.

Member loop structure (2000)

2000   INS  Member level detail   (subscriber/dependent, relationship, maintenance type/reason, benefit status)
       REF  Subscriber ID, member policy number
       DTP  Member-level dates (hire, eligibility begin)
  2100A NM1·IL Member Name        + PER, N3/N4 address, DMG (DOB/gender), LUI language
  2100C NM1   Member mailing / responsible person (situational)
  2200  DSB  Disability (situational)
  2300  HD   HEALTH COVERAGE      (maintenance type, insurance line: HLT/DEN/VIS/…)
        DTP  Coverage begin/end dates
        REF  Health coverage policy / plan ID
        COB  Coordination of benefits (situational)
        LX/  Additional reporting (provider, etc.)

Key segments

Segment	Carries
`BGN`	transaction purpose (original/reissue/reinstate), reference ID, timestamp, action code (full vs change)
`N1·P5` / `N1·IN`	sponsor (employer) and insurer/payer identification
`INS`	member maintenance: subscriber/dependent (Y/N), relationship code, maintenance type (021 add, 024 terminate, 001 change, 025 reinstate), maintenance reason, benefit status
`REF`	subscriber number, group/policy numbers
`NM1·IL`	member name + identifier (SSN/member ID)
`DMG`	date of birth, gender, marital status
`HD`	health coverage: maintenance type + insurance line code (HLT, DEN, VIS, etc.) + plan coverage description
`DTP`	eligibility/coverage begin and end dates

Data rules

INS maintenance type code drives the action: 021 add, 001 change, 024 termination, 025 reinstatement, 030 audit/compare. The HD maintenance type mirrors this at the coverage level.
Subscriber vs dependent: INS01 (Y/N) marks the subscriber; INS02 relationship code (18 self, 01 spouse, 19 child…) ties dependents to the subscriber. Dependents reference the subscriber ID in REF.
Full file vs change file (BGN08): a full file is a complete replace; a change file carries only deltas. The payer companion guide dictates which is expected and the reconciliation method.
Coverage dates (DTP in 2300/2000) set begin/end; terminations require an end date consistent with the maintenance reason.
Envelope control numbers (ISA/GS/ST) must match trailers; SE segment count must be exact.

Worked example (add one subscriber with dependent — skeleton)

ST*834*0001*005010X220A1~
BGN*00*REF20250531*20250531*1200****2~          Original, change file (2)
REF*38*GRP00123~                                 Master policy / group
DTP*303*D8*20250601~                             File effective date
N1*P5*ACME EMPLOYER*FI*123456789~                Sponsor
N1*IN*BCBS*FI*987654321~                         Payer
INS*Y*18*021*XN*A***FT~                          Subscriber, ADD (021), active full-time
REF*0F*SUB100~                                    Subscriber ID
NM1*IL*1*DOE*JANE****34*123456789~               Member name (SSN)
DMG*D8*19850115*F~                               DOB / gender
HD*021**HLT*PLANGOLD~                            Coverage ADD: health, plan GOLD
DTP*348*D8*20250601~                             Coverage begin
INS*N*01*021*XN*A~                               Dependent (spouse), ADD
REF*0F*SUB100~                                    Links to subscriber SUB100
NM1*IL*1*DOE*JOHN****34*223456789~
DMG*D8*19840320*M~
HD*021**HLT*PLANGOLD~
DTP*348*D8*20250601~
SE*19*0001~                                      19 segments, ST and SE inclusive

(Subscriber INS01=Y relationship 18=self; dependent INS01=N relationship 01=spouse linked by REF*0F*SUB100; both maintenance type 021 = add, coverage begins 2025-06-01.)

Validation checklist

Version 005010X220A1 and the payer/exchange companion guide confirmed; full-file vs change-file (BGN08) correct
Sponsor (N1·P5) and payer (N1·IN) identifiers present
Each member has INS with correct maintenance type (021/001/024/025) and relationship code
Dependents reference the subscriber ID; subscriber flagged INS01=Y
NM1·IL name + member identifier and DMG (DOB/gender) present
HD coverage line codes and plan IDs valid; DTP begin/end dates consistent with the action
Terminations carry an end date and reason; reinstatements use 025
Envelope control numbers match trailers; SE count exact; passes 5010 validation before send

Last updated: 2026-05-31 — verify loop/segment usage, maintenance/relationship code sets, and full-vs-change file handling against the current ASC X12 005010X220A1 (834) TR3 and the payer/exchange companion guide before use.