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CARC Code Reference

CARC A8: Ungroupable DRG.

Ungroupable DRG.

Group code CO or PI
Category Benefit Maximum/Limitation
Risk level Medium
Appealable Review Required

Common RARC pairings

RARCs (Remittance Advice Remark Codes) provide the specific reason detail alongside CARC A8 on the 835 electronic remittance. These are the RARCs seen most often with this CARC.

RARCMeaning
N647 Adjusted based on diagnosis-related group (DRG).
N657 This should be billed with the appropriate code for these services.

See the full resolution workflow for CARC A8

Members of the EDI-Code Intelligence Lab get the step-by-step rework path, appeal language, root-cause drivers, and prevention checklist for every CARC and RARC pairing, plus payer-specific quirks.

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