CO Denial Codes

All CO Denial Codes

CO Denial Codes 1-20

CO-4 Denial Code- Indicates the procedure code conflicts with the billing modifier submitted on the claim

CO-5 Denial Code- Indicates the billed procedure is inconsistent with the reported place of service

CO-6 Denial Code- Indicates the billed procedure is inconsistent with the patient’s age according to payer guidelines

CO-8 Denial Code- indicates the billed procedure is inconsistent with the provider specialty or billing classification

CO-1 Denial Code- Indicates a deductible-related adjustment was applied during claim processing

CO-2 Denial Code- Indicates the payer determined the billed procedure is not covered under the patient’s insurance plan

CO-3 Denial Code- Indicates the payer determined the billed procedure does not qualify for reimbursement under insurance coverage guidelines

CO-7 Denial Code- Indicates the payer determined the billed procedure is inconsistent with the submitted diagnosis or reimbursement guidelines.

CO-9 Denial Code- Indicates the patient was not eligible for insurance benefits on the date of service

CO-10 Denial Code- Indicates the payer identified invalid, incomplete, or inconsistent billing information during claim processing.

CO-11 Denial Code- Indicates the diagnosis submitted on the claim does not properly support the billed procedure.

CO-12 Denial Code- Indicates the claim was denied do to the billed procedure or service is inconsistent with payer coding or reimbursement guidelines

CO-13 Denial Code- Indicates insurance determined the billed procedure does not qualify for reimbursement under the patient’s insurance coverage

CO-14 Denial Code- Indicates the insurance payer identified missing claim information required for reimbursement processing

CO-15 Denial Code- Indicates missing or invalid authorization information on the claim

CO-16 Denial Code- Indicates missing or incomplete claim information.

CO-17 Denial Code- Indicates the payer requires additional information or documentation before claim reimbursement can be processed

CO-18 Denial Code- Indicates the payer considers the submitted claim a duplicate

CO-19 Denial Code- Indicates the payer considers the billed service a duplicate of a previously processed service

CO-20 Denial Code- Indicates another insurance payer is responsible for processing the claim first

CO-21 Denial Code- Indicates the service is covered under a capitation agreement or managed care arrangement

CO Denial Codes 21-40

CO-22 Denial Code- Indicates another insurance payer may be responsible for the claim

CO-23 Denial Code- Indicates another payer has already made payment on the claim

CO-24 Denial Code- Indicates the service is covered under a capitation agreement or managed care arrangement

CO-25 Denial Code- Indicates the payer considers the service included in another payment and separate reimbursement is not allowed

CO-26 Denial Code- Indicates expenses were incurred before the patient's insurance coverage became effective

CO-45 Denial Code- Indicates the billed charge exceeds the payer's allowable amount

CO Denial Codes 41-60

CO-97 Denial Code- Indicates the billed service is included in the payment for another procedure

CO Denial Codes 81-100

CO-122 Denial Code- Psychiatric reduction applied

CO Denial Codes 121-140

CO-123 Denial Code- Payer reimbursement policy adjustment

CO-124 Denial Code- Coverage Policy Adjustment

CO-243 Denial Code- Indicates the service was not properly authorized before treatment was provided

CO Denial Codes 241-260

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