CO-P4: Workers' Compensation Claim Non-Compensable
CO-P4 means the WC claim is non-compensable. Appeal through the WC process or redirect to health insurance.
What Does CO-P4 Mean?
When paired with Group Code CO, the WC carrier determined the claim is non-compensable. The provider cannot bill the WC carrier further. Redirect to health insurance or appeal through the WC dispute process.
CARC P4 indicates the workers' compensation carrier adjudicated the claim as non-compensable, meaning the injury or illness does not qualify for WC benefits under applicable state law. This is different from P2 (not work-related) — P4 specifically means the WC carrier reviewed and determined the claim does not meet the criteria for compensability under the state's WC statute.
Reasons for non-compensability include the employer disputing the claim, the treatment not being causally related to the accepted work injury, the WC benefits not being available for this type of treatment under state law, or the claim failing to meet procedural requirements for compensability.
The appeal path is through the state workers' compensation dispute resolution process, not through the standard insurance appeal process. If the claim is legitimately non-compensable, redirect it to the patient's health insurance.
Common Causes
| Cause | Frequency |
|---|---|
| WC claim adjudicated as non-compensable The workers' compensation carrier determined the claim is non-compensable — the injury/illness does not qualify for WC benefits under applicable state law | Most Common |
| Employer disputed the WC claim The employer contested the WC claim and the carrier adjudicated it as non-compensable | Common |
| Treatment not causally related to work injury The treatment billed is not causally related to the accepted work injury, making the WC carrier not liable | Common |
| WC benefits exhausted or not applicable The WC benefits for this type of treatment are not available under the state's WC statute | Occasional |
How to Resolve
- Review determination Understand the non-compensability basis.
- Appeal through WC process File a formal WC dispute with supporting documentation.
- Redirect to health insurance If non-compensable, bill the patient's health insurance.
Appeal through the state workers' compensation dispute process. Include the incident report, employer's First Report of Injury, physician's causation opinion linking the treatment to the work injury, and relevant medical records. If the employer disputed the claim, provide evidence supporting work-relatedness.
Common RARC Pairings
The RARC code tells you exactly what triggered the CO-P4:
| RARC | Description |
|---|---|
| N381 | Alert: Consult your contractual agreement for restrictions, billing, and payment information. Review the WC non-compensability determination and redirect the claim to the patient's health insurance → |
How to Prevent CO-P4
- Verify WC claim compensability status before providing treatment
- Confirm WC claim acceptance with the employer and carrier before billing WC
- Collect both WC and health insurance information from patients with workplace injuries
- Document the causal relationship between the work injury and the treatment provided
- Monitor WC claim status throughout the treatment period
Also Filed As
The same CARC P4 may appear with different Group Codes:
Related Denial Codes
Sources
- https://x12.org/codes/claim-adjustment-reason-codes
- https://www.cms.gov/medicare/coordination-benefits
- Codes maintained by X12. Visit x12.org for official definitions.