Denial catagories

We most often receive denials from insurance companies in two main categories: CO and PR. Occasionally, denials may also be received under the OA category.

CO (Contractual Obligation): This indicates that the amount adjusted (denied) is based on the contract between the provider and the insurance, and it is never the patient’s responsibility. Any amount with a CO category code cannot be billed to the patient.

PR (Patient Responsibility): This indicates that the amount with a PR category code is the patient’s responsibility. The patient owes this amount, and neither the insurance, provider, nor any other party is responsible for it. However, when billing the patient, only copay, coinsurance, deductible, or paid-to-patient amounts should be billed. For out-of-network (OON) providers, every denial or adjustment comes with a PR category, but these denials or adjustments should never be billed directly to the patient without review. Instead, take the proper required action as per guidelines. If you must bill any other PR denial to the patient, first consult with the client or follow the practice SOPs.

OA (Other Adjustments): This category includes adjustment codes that do not fit into any other category, such as CO or PR.

Below is a list of the most common denials in medical billing. Click on each denial to view its reason, description, and the proper corrective action.

Denial codes

• 1: Deductible.

• 2: Coinsurance.

• 3: Copay.

• 4: Inconsistent / Missing modifier.

• 5: Procedure code is inconsistent with place of service.

• 6: Procedure/Revenue code is inconsistent with patient's age.

• 7: Procedure code is inconsistent with patient gender.

• 8: Procedure is inconsistent with provider taxonomy.

• 9: Diagnosis is inconsistent with patient's age.

• 10: Diagnosis is inconsistent with patient's gender.

• 11: Diagnosis is inconsistent with procedure.

• 12: Diagnosis is inconsistent with the provider taxonomy.

• 13: Date of death precedes DOS.

• 14: DOS Precedes DOB(date of birth).

• 16: Lack of information in claim.

• 18: Exact duplicate service/claim.

• 19: Liability of worker's compensation as it is a work related injury/illness.

• 20: This injury/illness is covered by liability carrier.

• 21: This illness/injury is liability of no-fault carrier.

• 22: Covered by another payer per COB (coordination of benefits).

• 23: Impact of prior payer.

• 24: Charges covered under capitation agreement.

• 26: Expenses incurred prior to the coverage start.

• 27: Expenses incurred after coverage terminated.

• 29: Timely filing limit (TFL) expired.

• 31: Patient cannot be identified as our insured.

• 45: Charges exceeds maximum allowable fee schedule.

• 49: Noncovered as it is routine/preventive exam or screening procedure done in conjunction to routine/preventive exam.

• 50: Services not deemed as medical necessity by the payer.

• 51: Services are noncovered as this is a pre existing condition.

• 55: Services/Drug deemed as experimental or investigational by the payer.

• 96: Noncovered services (Unspecified).

• 97: Payment for this service Bundled/Inclusive with other service already been adjudicated.

• 100: Payment made to subscriber/patient or responsible person.

• 109: Services not covered by this payer, you must send them to correct payer/insurance.

• 119: Maximum benefits has been reached.

• 129: Prior processing information appears incorrect.

• 140: Patient/Subscriber's identification number or name mismatched.

• 146: Invalid diagnosis for the DOS.

• 150: Information submitted doesn't support this level of service.

• 151: Information submitted doesn't support this many/frequency of service.

• 163: Attachment or other documentation referenced on the claim was not received.

• 181: Procedure code was invalid on DOS.

• 182: Modifier was invalid on DOS.

• 183: Referring provider is not eligible to refer for the service billed.

• 185: Rendering provider is not eligible to perform the service billed.

• 197: Precertification/authorization absent.

• 199: Revenue code and procedure code mismatched.

• 226: Information requested from billing/rendering provider was either received after allowed time or incomplete or yet not receive.

• 227: Information requested from patient/subscriber was not provided or was insufficient/incomplete.

• 234: This procedure is not paid separately.

• 236: This procedure or procedure/modifier combination is not compatible with other procedure or procedure/modifier combination.

• 242: Services not provided by network/primary care physician.

• 252: Missing documentation.

• 288: Referral absent.

• B7: Provider is not eligible to be paid for this service on this DOS.

• B9: Patient enrolled in Hospice.

• B16: New patient qualifications were not met.

• B20: Procedure or service was fully or partially performed by another provider.

• M119: Missing/Incomplete/Invalid National Drug Code (NDC).

• MA120: Missing/Incomplete/Invalid CLIA certification number.

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