Insurance denial codes — full reference
Every CARC, RARC, and group code that appears on an EOB or ERA, with plain-language explanations and a clear yes/no on appealability. Updated quarterly against the current X12 publication.
Claim Adjustment Reason Codes
194 codes — official X12 description, plain-language meaning, group, and appealability. Includes every code in the appealable set DenialHelp recognises in the intake pipeline.
CO / PR / OA / PI explained
Group codes tell you who owes the money. Contractual Obligation, Patient Responsibility, Other Adjustment, Payer Initiated Reductions — what each means and how to read your EOB.
Frequently asked questions
Where do I find the denial code on my EOB?
On a patient EOB, the denial reason appears in a column labelled 'Reason', 'Adjustment Code', 'Notes', or similar. The code is typically 1-3 digits, sometimes preceded by a group code letter pair (e.g., CO-50 means group code CO, reason code 50). On the 835 ERA the codes are in the CAS segments (group code + reason code + amount).
Which code do I look up first?
Look up the CARC (the numeric reason code, e.g., 50, 197, 204) first — that's the primary reason. Then check the group code (CO, PR, OA, PI) to know who owes the money. RARC codes are supplementary and add detail.
Are all denial codes appealable?
No. Codes that involve clinical judgement (medical necessity, experimental, prior auth) are typically appealable. Codes that reflect contractual write-offs, normal patient cost-sharing (deductible, copay, coinsurance), or routine accounting usually aren't. Each code page on DenialHelp shows whether the code is typically appealable.
Sources
Contact: hello@denialhelp.com