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Denial Codes (CARC)

What each denial code means, the fix, and the appeal path. 47 entries.

CO-4 Denial Code: Procedure Code Inconsistent With Modifier

CO-4 is a claim adjustment reason code meaning the procedure code is inconsistent with the modifier used, or a required…

CO-6 Denial Code: Procedure/Revenue Code Inconsistent With Patient Age

CO-6 is a claim adjustment reason code meaning the procedure or revenue code is inconsistent with the patient's age. It…

CO-11 Denial Code: Diagnosis Inconsistent With the Procedure

CO-11 means the diagnosis is inconsistent with the procedure — the ICD-10 code on the claim does not logically support …

CO-15 Denial Code: Missing, Invalid, or Inapplicable Authorization Number

CO-15 is a claim adjustment reason code meaning the authorization number is missing, invalid, or does not apply to the …

CO-16 Denial Code: Claim Lacks Information or Has Submission Errors

CO-16 means the claim or service lacks information or has submission/billing errors. It never travels alone: the accomp…

CO-18 Denial Code: Exact Duplicate Claim or Service

CO-18 is a claim adjustment reason code meaning the payer received an exact duplicate claim or service: same patient, p…

CO-19 Denial Code: Work-Related Injury, Liability of Workers' Compensation Carrier

CO-19 means this is a work-related injury or illness and thus the liability of the Workers' Compensation carrier — the …

CO-22 Denial Code: Care May Be Covered by Another Payer (Coordination of Benefits)

CO-22 is a claim adjustment reason code meaning this care may be covered by another payer per coordination of benefits.…

CO-23 Denial Code: Impact of Prior Payer(s) Adjudication

Code 23 means the adjustment reflects the impact of prior payer(s) adjudication, including payments and/or adjustments.…

CO-24 Denial Code: Charges Covered Under a Capitation Agreement or Managed Care Plan

CO-24 is a claim adjustment reason code meaning charges are covered under a capitation agreement or managed care plan. …

CO-27 Denial Code: Expenses Incurred After Coverage Terminated

CO-27 is a claim adjustment reason code meaning expenses were incurred after the patient's coverage terminated. The pol…

CO-29 Denial Code: The Time Limit for Filing Has Expired

CO-29 means the time limit for filing has expired — the claim arrived after the payer's timely filing deadline. Medicar…

CO-31 / PR-31 Denial Code: Patient Cannot Be Identified As Our Insured

CARC 31 means the patient cannot be identified as the payer's insured — the demographic or member ID data submitted did…

CO-45 Denial Code: Charge Exceeds Fee Schedule / Maximum Allowable

CO-45 means the charge exceeds the fee schedule, maximum allowable, or contracted/legislated fee arrangement. It is a c…

CO-50 Denial Code: Non-Covered Services Not Deemed Medically Necessary

CO-50 means the payer denied the service as not medically necessary — the diagnosis on the claim does not justify the p…

CO-59 Denial Code: Processed Based on Multiple or Concurrent Procedure Rules

CO-59 means the service was processed under multiple or concurrent procedure rules — multiple surgery, diagnostic imagi…

CO-96 Denial Code: Non-Covered Charge(s)

CO-96 is a claim adjustment reason code meaning non-covered charge(s): the service is excluded from the patient's benef…

CO-97 Denial Code: Benefit Included in Payment for Another Service

CO-97 means the benefit for this service is included in the payment or allowance for another service already adjudicate…

CO-107 Denial Code: Related or Qualifying Claim/Service Not Identified

CO-107 means the related or qualifying claim or service was not identified on this claim — a billed service depends on …

CO-109 Denial Code: Claim/Service Not Covered by This Payer/Contractor

CO-109 is a claim adjustment reason code meaning the claim or service is not covered by this payer or contractor and mu…

CO-119 Denial Code: Benefit Maximum for This Time Period Reached

CO-119 is a claim adjustment reason code meaning the benefit maximum for this time period or occurrence has been reache…

CO-131 Denial Code: Claim Specific Negotiated Discount

CO-131 means a claim specific negotiated discount was applied — the provider and payer agreed to an allowance below bil…

CO-140 / PR-140 Denial Code: Patient/Insured ID Number and Name Do Not Match

CARC 140 means the patient or insured health identification number and name do not match the payer's records — a data-v…

CO-146 Denial Code: Diagnosis Was Invalid for the Date(s) of Service

CO-146 means the diagnosis was invalid for the date(s) of service reported — the ICD-10 code was expired, not yet effec…

CO-151 Denial Code: Information Does Not Support This Many/Frequency of Services

CO-151 is a claim adjustment reason code meaning payment was adjusted because the payer deems the submitted information…

CO-167 Denial Code: Diagnosis(es) Not Covered

CO-167 is a claim adjustment reason code meaning this diagnosis or these diagnoses are not covered. The ICD-10 code on …

CO-170 Denial Code: Payment Denied When Performed/Billed by This Type of Provider

CO-170 is a claim adjustment reason code meaning payment is denied when performed or billed by this type of provider. T…

CO-181 Denial Code: Procedure Code Was Invalid on the Date of Service

CO-181 means the procedure code was invalid on the date of service — the CPT or HCPCS code was expired, not yet effecti…

CO-183 Denial Code: Referring Provider Not Eligible to Refer the Service Billed

CO-183 means the referring provider is not eligible to refer the service billed — the referring NPI on the claim is mis…

CO-197 Denial Code: Precertification/Authorization/Notification Absent

CO-197 is a claim adjustment reason code meaning precertification, authorization, notification, or pre-treatment requir…

CO-198 Denial Code: Precertification/Notification/Authorization Exceeded

CO-198 is a claim adjustment reason code meaning precertification, notification, authorization, or pre-treatment limits…

CO-204 Denial Code: Service Not Covered Under the Patient's Benefit Plan

CO-204 means the service, equipment, or drug is not covered under the patient's current benefit plan. With the CO group…

CO-231 Denial Code: Mutually Exclusive Procedures Same Day or Setting

CO-231 means mutually exclusive procedures cannot be done in the same day or setting. The payer paid one procedure and …

CO-236 Denial Code: Procedure or Modifier Combination Not Compatible (NCCI)

CO-236 means this procedure or procedure/modifier combination is not compatible with another combination billed the sam…

CO-252 Denial Code: Attachment or Other Documentation Required

CO-252 means an attachment or other documentation is required to adjudicate the claim — it is a records request, not a …

CO-B7 Denial Code: Provider Not Certified or Eligible on This Date of Service

CO-B7 means this provider was not certified or eligible to be paid for this procedure or service on this date of servic…

CO-B15 Denial Code: Qualifying Service Not Received or Adjudicated

CO-B15 means the billed service requires a qualifying service or procedure to be received and covered first, and that q…

OA-18 Denial Code: Exact Duplicate Claim or Service

OA-18 means exact duplicate claim/service — the payer already has a claim matching this patient, provider, date, code, …

OA-23 Denial Code: Impact of Prior Payer Adjudication

OA-23 means "the impact of prior payer(s) adjudication including payments and/or adjustments" — used only with Group Co…

PI-204 Denial Code: Service Not Covered Under the Patient's Benefit Plan

PI-204 pairs CARC 204 — service, equipment, or drug not covered under the patient's current benefit plan — with the Pay…

PR-1 Denial Code: Deductible Amount

PR-1 means Deductible Amount: the payer applied the allowed amount (or part of it) to the patient's unmet annual deduct…

PR-2 Denial Code: Coinsurance Amount

PR-2 is a claim adjustment reason code meaning coinsurance amount: the percentage of the allowed amount the patient owe…

PR-3 Denial Code: Co-payment Amount

PR-3 is a claim adjustment reason code meaning co-payment amount: the flat per-visit fee the patient owes under their p…

PR-27 Denial Code: Expenses Incurred After Coverage Terminated

PR-27 means expenses were incurred after coverage terminated — the patient's policy had ended before the date of servic…

PR-49 Denial Code: Non-Covered Routine / Preventive Exam or Screening

PR-49 means the service is non-covered because it is a routine/preventive exam or a screening procedure done in conjunc…

PR-119 Denial Code: Benefit Maximum for This Time Period or Occurrence Reached

PR-119 means the benefit maximum for this time period or occurrence has been reached — the patient has used up a capped…

PR-204 Denial Code: Service Not Covered Under the Patient's Benefit Plan

PR-204 means the service, equipment, or drug is not covered under the patient's current benefit plan, and the PR group …

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