What is RARC?
Also called: remittance advice remark code · N-codes
RARCs come in two forms: alphanumeric codes beginning with N or M, and informational codes that add context without changing the adjustment.
Denial workflows that route on CARC alone lose accuracy at exactly the codes that matter most. Routing on the CARC and RARC pair is what makes automated denial triage worth building.
Where Vizora handles this
Primary sources
Where "RARC" is defined by the bodies that set the rules, rather than by us.
- Remittance Advice Remark Codes (RARC) (opens in a new tab)
X12 — The remark codes that qualify a CARC on an ERA. Reading the RARC is usually what tells you whether a denial is appealable.
- Claim Adjustment Reason Codes (CARC) (opens in a new tab)
X12 — The authoritative, maintained CARC list. Our denial code lookup explains these in plain English; X12 is where the canonical definitions live.
Last reviewed August 20, 2026
Related terms
CARC
A claim adjustment reason code explains why a payer adjusted or denied a payment. Maintained by X12, each CARC carries a group code — CO for contractual obligation, PR for patient responsibility, OA for other adjustment — which determines whether the balance may be billed to the patient.
ERA
An electronic remittance advice, transmitted as an X12 835 file, is the payer's electronic explanation of how a claim was adjudicated. It reports what was allowed, what was paid, what was adjusted and why — using CARC and RARC codes — and it drives automated payment posting.
Denial
A denial is a claim the payer adjudicated and refused to pay. It differs from a rejection, which never entered adjudication. That distinction determines your remedy: a rejected claim is corrected and resubmitted, while a denied claim must be appealed within the payer's deadline.
Appeal
An appeal is a formal request that a payer reconsider a denied claim, supported by documentation addressing the stated denial reason. Commercial payers typically allow 90 to 180 days from the remittance date; Medicare provides five escalating levels beginning with redetermination within 120 days.
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