CO-22: Coordination of Benefits - Another Payer May Cover
Provider responsibility — correct and resubmit to the appropriate payer. The patient is not liable for this amount.
What Does CO-22 Mean?
With CO (Contractual Obligation), the CARC 22 adjustment for coordination of benefits - another payer may cover indicates the claim needs to be corrected or routed to a different payer. The patient is not liable for this amount. Correct the issue and resubmit.
CARC 22 indicates coordination of benefits - another payer may cover. The payer determined that the service or a portion of it does not meet coverage criteria under the patient's current plan benefits or the applicable coverage rules.
Common scenarios that trigger this adjustment include: claim submitted to the secondary payer without first billing the primary payer; The payer has outdated coordination of benefits data showing another primary payer; The claim is missing information about other insurance coverage the patient has. The group code paired with CARC 22 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
| Cause | Frequency |
|---|---|
| Wrong payer billed first Claim submitted to the secondary payer without first billing the primary payer | Most Common |
| Outdated COB information The payer has outdated coordination of benefits data showing another primary payer | Most Common |
| Missing other insurance details The claim is missing information about other insurance coverage the patient has | Common |
| Multiple active policies not coordinated Patient has multiple active insurance policies that were not properly coordinated | Common |
| Medicare Secondary Payer rules Medicare determined it is secondary to another payer based on MSP rules | Common |
How to Resolve
- Review the denial reason Examine the CO-22 adjustment and any RARC codes to identify what needs to be corrected.
- Correct the claim Address the issue that triggered the denial — update the claim with correct information or route to the appropriate payer.
- Resubmit the claim Submit the corrected claim per the payer's guidelines.
If the patient has no other insurance, appeal with a patient attestation of single coverage and updated eligibility information. If COB data is outdated, contact the payer to update the patient's file and resubmit.
Common RARC Pairings
The RARC code tells you exactly what triggered the CO-22:
| RARC | Description |
|---|---|
| MA04 | Secondary payment cannot be considered without primary payer information Obtain and submit primary payer EOB → |
| MA92 | Missing plan information for other insurance Provide the other insurance plan details → |
| N36 | Claim must meet primary payer requirements before secondary payment Submit to primary payer first → |
How to Prevent CO-22
- Verify insurance and COB information at every patient visit
- Train front desk staff on proper COB data collection
- Use real-time eligibility verification systems that check for other coverage
- Keep patient demographics and insurance data current
- Teach billing staff the birthday rule and MSP guidelines
- Run pre-submission claim scrubbers to catch COB errors
Also Filed As
The same CARC 22 may appear with different Group Codes:
Related Denial Codes
Sources
- https://x12.org/codes/claim-adjustment-reason-codes
- https://revenuecyclemgmt.com/claim-adjustment-reason-codes/
- https://medsolercm.com/blog/denial-codes-co-22-denial-code
- https://www.mdclarity.com/denial-code/22
- Codes maintained by X12. Visit x12.org for official definitions.