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Code index

All CARC + RARC denial codes

41 codes written in plain English so far — 31 CARC and 10 RARC. Filter by code or keyword, sort by type or appealability, and open any code for the full breakdown.

41 codes

Plain-English meaning
CO-109CARCCOThis insurer is not the right payer for this claim — it should go to a different plan or contractor.
CO-11CARCCOThe insurer says the diagnosis on the claim does not justify the procedure that was billed.
CO-119CARCCOYou have reached a benefit limit for this service in the current period (for example, a yearly visit cap), so no more is covered for now.
CO-146CARCCOThe diagnosis code on the claim was not valid for the date the service happened.
CO-147CARCCOThe insurer does not have a current contracted rate on file for this provider, so it could not price the claim normally.
CO-151CARCCOThe insurer paid for fewer units of this service than were billed, because it does not think the documentation supports the quantity.
CO-16CARCCOThe claim is missing required information or contains a billing error, so the insurer could not finish processing it. A Remittance Advice Remark Code (an N- or M- code) usually appears alongside this one to say exactly what is missing.
CO-167CARCCOThe diagnosis on the claim is not a covered condition under your plan for this service.
CO-18CARCCOThe insurer believes this exact claim or service was already submitted, so it was not paid a second time.
CO-197CARCCOA required prior authorization or pre-certification was not on file before the service, so the claim was denied.
CO-198CARCCOCare was authorized, but the services billed went beyond what the authorization allowed.
CO-204CARCCOThis specific service, equipment, or drug is not a benefit under your current plan.
CO-22CARCCOThe insurer believes another insurance plan should pay before it does, under coordination-of-benefits rules.
CO-24CARCCOThese charges fall under a capitation arrangement — the provider is paid a set per-member fee by the managed-care plan, so this service is not billed separately.
CO-252CARCCOThe insurer needs additional documentation (such as medical records) before it can decide the claim. A remark code usually says exactly what.
CO-29CARCCOThe claim was submitted after the insurer's filing deadline, so it was not paid.
CO-31CARCCOThe insurer could not match you to an active policy with the information on the claim.
CO-4CARCCOThe insurer says the billing modifier attached to the procedure does not match the procedure code itself.
CO-45CARCCOThe provider billed more than the insurer's contracted or allowed amount. For in-network care, the difference is written off and is not your responsibility.
CO-5CARCCOThe procedure billed does not line up with the place of service code (for example, an inpatient code billed for an office visit).
CO-50CARCCOThe insurer decided this service was not medically necessary under your plan's criteria, so it was not covered.
CO-96CARCCOThis service is not covered under your plan. An accompanying remark code usually explains why.
CO-97CARCCOThis service is bundled into the payment for another service that was already processed, so it is not paid separately.
CO-A1CARCCOA general denial. On its own, A1 does not say why — there should be an accompanying remark code (N- or M-) that explains the specific reason.
CO-B7CARCCOOn the date of service, the provider was not certified or eligible with the insurer to be paid for this service.
M15RARCServices that were billed separately were combined (bundled) because the insurer treats them as parts of one procedure, so they are not paid separately.
M51RARCThe procedure code on the claim is missing, incomplete, or not valid.
M76RARCThe diagnosis or condition on the claim is missing, incomplete, or not valid.
MA01RARCA Medicare alert about your appeal rights: you can appeal in writing, a different reviewer will handle it, and you generally have 120 days from the notice date to file.
MA130RARCThe claim could not be processed because it was incomplete or invalid. There are no appeal rights for an unprocessable claim — instead, a corrected new claim must be submitted.
N1RARCThis is an alert telling you that you have the right to appeal this decision in writing, within the time limits set by your plan or state law.
N115RARCThis Medicare decision was based on a Local Coverage Determination — a regional Medicare policy that defines when an item or service is covered.
N130RARCThe insurer is pointing you to your plan documents to understand the coverage restrictions that applied to this service.
N30RARCThe insurer's records show you were not eligible for this specific service under your plan.
N4RARCThe insurer needs the Explanation of Benefits from your other (primary) insurance and did not receive a complete, valid copy.
OA-23CARCOAThis adjustment reflects what a prior insurer already paid or adjusted. It is an accounting line showing the effect of the primary payer's decision, not a new denial.
PR-1CARCPRThis amount was applied to your plan deductible — the amount you pay out of pocket each year before your insurer starts paying its share.
PR-2CARCPRThis is your coinsurance — the percentage share of the allowed amount you owe after your deductible is met (for example, 20% of the bill).
PR-26CARCPRThe service happened before your coverage started, so the plan did not pay for it.
PR-27CARCPRThe service happened after your coverage ended, so the plan did not pay for it.
PR-3CARCPRThis is your copay — a fixed dollar amount you owe for this type of visit or service (for example, a set fee per office visit).