Submit an X12 270 eligibility inquiry and parse the 271 response via a clearinghouse API

Verified steps

1. Obtain API credentials from a clearinghouse (e.g., Availity, Change Healthcare/Optum, Stedi, or similar); most provide REST APIs that accept and return X12 EDI transactions or structured JSON equivalents.
2. Construct the 270 eligibility inquiry with the required segments: ISA (interchange header), GS (functional group header), ST (transaction set header, type 270), BHT (beginning of hierarchical transaction), HL segments for information source (payer), subscriber, and dependent levels, EQ segment for the requested benefit type.
3. Include key subscriber data in NM1/DMG segments: NM1*IL (subscriber), member ID in NM1-09, and DMG for date of birth and gender; include the payer NM1*PR with the payer ID.
4. POST the 270 transaction to the clearinghouse API endpoint; real-time eligibility checks typically return the 271 response synchronously within seconds; batch submissions use async polling.
5. Parse the 271 response: locate EB segments (eligibility benefit information) which contain benefit type codes, coverage level, in/out-of-network status, co-pay, deductible, and out-of-pocket amounts; MSG segments contain human-readable notes.
6. Map EB-01 (eligibility benefit information code) to human-readable descriptions (e.g., '1'=Active Coverage, '6'=Inactive, 'C'=Deductible, 'G'=Out-of-Pocket) using the X12 code list.