Parse Health Care Remittance EDI (X12 835)

Skill: Convert an X12 835 remittance advice into postable A/R data

Region: United States Category: Health Care EDI (HIPAA X12 5010) Does: Takes a payer's ASC X12N 835 Health Care Claim Payment/Advice (ERA) and parses it into structured, postable accounts-receivable data — what the payer paid per claim and service line, why amounts were adjusted, and how the electronic payment reconciles. Spec: ASC X12 005010 — 835 005010X221A1

The 835 is the HIPAA-mandated electronic remittance advice (ERA) that pairs with the 837 claim; it is governed by its X12 TR3. The 835 is read/parsed (payer→provider), not authored by the provider. Adjustment meaning comes from the CARC/RARC code lists (Claim Adjustment Reason Codes / Remittance Advice Remark Codes) maintained by the X12 code-list committees — always resolve codes against the current lists.

Transaction envelope

ISA / GS (FG = HP, version 005010X221A1) / ST (835)
  BPR  Financial information (payment method, amount, ACH/CCP+ trace)
  TRN  Reassociation Trace Number  (links the EFT to this 835)
  ... payer / payee / claim / service loops ...
SE / GE / IEA

BPR + TRN let the provider reassociate the 835 with the actual ACH/EFT deposit (the TRN02 trace number appears in the bank's CCD+ addenda).

Loop / segment structure

1000A  Payer Identification   (N1·PR, N3/N4, PER contacts)
1000B  Payee Identification   (N1·PE, REF payee NPI/TIN)
2000   Header Number / provider summary  (LX, TS3/TS2 provider totals)
  2100  CLAIM PAYMENT INFO  (CLP)         — one per claim
        CLP  claim status, charge, paid, patient responsibility, payer claim control no.
        NM1  patient / insured / corrected
        CAS  CLAIM-LEVEL ADJUSTMENTS  (group code + CARC + amount[+quantity]…)
        REF  other claim identifiers
        DTP  claim dates
    2110  SERVICE PAYMENT INFO  (SVC)     — one per service line
          SVC  procedure (CPT/HCPCS), line charge, line paid, units
          CAS  SERVICE-LEVEL ADJUSTMENTS (group code + CARC + amount)
          AMT  allowed / other amounts
          LQ   remark codes (RARC)
PLB  Provider-Level Adjustments (after all claims — e.g. withholding, interest, refunds)

Key segments

Reconciliation rules

• Per service line: line charge = line paid + Σ line CAS adjustments. Each CAS triple is group code + reason code (CARC) + amount.
• Group codes assign responsibility: CO = contractual obligation (provider write-off), PR = patient responsibility (bill the patient), OA = other adjustment, PI = payer initiated, CR = correction/reversal.
• Per claim: the CLP paid amount + patient responsibility + claim-level adjustments should reconcile to the submitted charge; service-line totals roll up to the claim.
• Whole remittance: BPR02 total payment = Σ claim paid amounts − Σ PLB provider-level adjustments. The TRN02 trace must match the EFT addenda for auto-posting.
• CARC/RARC codes drive A/R logic — e.g. CO-45 (charge exceeds fee schedule → write-off), PR-1 (deductible → patient), PR-2 (coinsurance), PR-3 (copay).

Worked example (one claim, one line — parsed)

BPR*I*100.00*C*ACH*CCP*...*20250531~      Total EFT $100.00 via ACH
TRN*1*1234567890*1999999999~              Trace number for reassociation
CLP*PATCTL001*1*125*100*25*12*PAYERCTL55*11~   Charge 125, paid 100, patient resp 25, status 1 (processed as primary)
CAS*PR*1*25~                              $25 → patient responsibility (deductible, CARC 1)
SVC*HC:99213*125*100**1~                  CPT 99213: charge 125, paid 100
CAS*CO*45*0~                              (contractual; example shows allowed = charge)
AMT*B6*100~                               Allowed amount 100

Parsed result → post $100 payment to claim PATCTL001, bill patient $25 (PR-1 deductible), payer claim control PAYERCTL55; reassociate via trace 1234567890 against the $100 ACH deposit.

Validation / posting checklist

• ISA/GS/ST envelope parsed; version 005010X221A1 confirmed; SE segment count consistent
• BPR payment amount and method captured; TRN trace stored for EFT reassociation
• Each CLP mapped to the original claim by payer claim control number / patient control number
• CAS adjustments split by group code (CO write-off vs PR patient-billable) and CARC resolved
• Per line: charge = paid + Σ adjustments; per claim totals roll up; remittance ties to BPR02 − PLB
• CARC/RARC codes resolved against the current code lists; secondary-payer balances routed for COB
• PLB provider-level adjustments posted separately (not against a single claim)
• Trace number matched to the bank EFT before auto-posting

Last updated: 2026-05-31 — verify segment usage against the current ASC X12 005010X221A1 (835) TR3, and resolve all adjustments against the current CARC/RARC code lists, before posting.