CO-6: Procedure/Revenue Code Inconsistent with Patient Age

What Does CO-6 Mean?

With CO (Contractual Obligation), the CARC 6 adjustment is the provider's responsibility. The payer denied or reduced payment because of patient's date of birth is entered incorrectly in the system, causing age calculation errors. The patient is not liable for this amount. If the denial is in error, the provider can correct and resubmit the claim or file an appeal with supporting documentation.

CARC 6 appears on a remittance when the payer identifies an issue related to procedure/revenue code inconsistent with patient age. This is a technical billing or coding problem that must be corrected before the claim can be processed for payment. The denial indicates the claim data did not meet the payer's adjudication requirements.

Common scenarios that trigger this adjustment include: patient's date of birth is entered incorrectly in the system, causing age calculation errors; Procedure code has age limits that do not match the patient's actual age (e.g., pediatric code for adult patient); Coder selected a CPT code with age restrictions when an age-appropriate alternative exists. The group code paired with CARC 6 determines who bears the financial responsibility — CO places it on the provider as a contractual obligation, OA indicates a coordination of benefits or other payer adjustment, PR shifts it to the patient.

Common Causes

How to Resolve

1. Review the remittance details Examine the CO-6 adjustment and any accompanying RARC codes to identify the specific reason for the denial.
2. Identify the root cause Determine which issue applies: incorrect date of birth on file, age-restricted procedure billed incorrectly, wrong CPT code selected, among others.
3. Correct the claim Address the identified issue — update the claim data in your billing system to resolve the procedure/revenue code inconsistent with patient age problem.
4. Resubmit the corrected claim Submit the corrected claim following the payer's resubmission guidelines. Include any supporting documentation that addresses the denial reason.
5. Appeal if the original claim was correct If both the patient's age and procedure code are correct, appeal with documentation including patient's ID/DOB verification and medical necessity for the procedure at that age. Resubmission with corrected data is typically faster.

Common RARC Pairings

The RARC code tells you exactly what triggered the CO-6:

How to Prevent CO-6

• Verify patient date of birth at every visit during registration
• Configure billing software to flag age-restricted procedure codes
• Train coders on age-specific CPT code requirements
• Implement pre-submission edits that check age against procedure codes
• Maintain accurate patient demographic data

Also Filed As

The same CARC 6 may appear with different Group Codes:

Related Denial Codes