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Paste your EOB denial code

Type or paste any CARC or RARC code from your Explanation of Benefits. The lookup runs entirely in your browser — nothing is sent anywhere.

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CO-109CARCCOContractual ObligationThis insurer is not the right payer for this claim — it should go to a different plan or contractor.CO-11CARCCOContractual ObligationThe insurer says the diagnosis on the claim does not justify the procedure that was billed.CO-119CARCCOContractual ObligationYou 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-16CARCCOContractual ObligationThe 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-18CARCCOContractual ObligationThe insurer believes this exact claim or service was already submitted, so it was not paid a second time.CO-197CARCCOContractual ObligationA required prior authorization or pre-certification was not on file before the service, so the claim was denied.CO-204CARCCOContractual ObligationThis specific service, equipment, or drug is not a benefit under your current plan.CO-22CARCCOContractual ObligationThe insurer believes another insurance plan should pay before it does, under coordination-of-benefits rules.CO-252CARCCOContractual ObligationThe insurer needs additional documentation (such as medical records) before it can decide the claim. A remark code usually says exactly what.

Reading the code

What the Group Code prefix tells you

A CARC usually travels with a two-letter Group Code. It is the fastest signal for whether an amount is yours to pay.

PRPatient Responsibility: Patient Responsibility — an amount the patient owes, such as a deductible, copay, coinsurance, or non-covered service.
COContractual Obligation: Contractual Obligation — an adjustment the provider agreed to by contract. The patient is generally not billed for CO amounts.
OAOther Adjustment: Other Adjustment — used when neither CO nor PR applies, often for coordination-of-benefits accounting between payers.
PIPayer Initiated: Payer Initiated Reduction — an adjustment the payer believes is justified but that is not a patient or contractual responsibility.