Workers Compensation Claim Denials
Overview
Workers' compensation is regulated by state workers' compensation commissions. Filing deadlines, prior authorization requirements, and denial procedures are set at the state level with no national standard. Common denials include CO-16 (late submission), CO-50 (not work-related or denied at payer discretion), and CO-29 (missing injury documentation). Appeals are filed with the state workers' compensation board, not private insurers. Medical causation must be established: the injury or treatment must connect directly to a work-related event.
Key Requirements
- State-Specific Filing Deadline: Each state sets its own claim filing deadline. There is no national standard. Contact your state workers' compensation commission for the deadline in your jurisdiction.
- Work-Related Injury Requirement: The injury must occur during employment. Document the date, time, and circumstances of the work injury in medical records.
- Medical Causation Documentation: Include clinical evidence connecting the treatment to the work injury. Physician notes must state that the service is treatment for the work-related condition.
- Prior Authorization: Most states require prior authorization for non-emergency procedures. File requests with the workers' compensation insurer before service delivery.
Timeline & Process
Report the work injury to the employer immediately (typically within 24 hours). File the workers' compensation claim with the state-designated insurer within your state's deadline. Include documentation of the work injury and clinical records. Request prior authorization for planned procedures 5–10 business days before service. File claims for treatment within your state's deadline (typically 30–90 days from service date). If a claim is denied, file an appeal with the state workers' compensation board within the state-specific appeal window (typically 30–60 days).
Common Denials
| Code | Reason |
|---|---|
| CO-16 | Claim submitted after state filing deadline. |
| CO-50 | Claim denied at payer discretion (typically: injury not deemed work-related). |
| CO-29 | Missing documentation of work injury or medical causation. |
Appeal Process
File written appeals with the state workers' compensation board listed on the denial notice. Include the claim number, detailed explanation of why the denial is incorrect, and supporting medical documentation. For work-related denials, include evidence that the injury occurred at work. For late filing denials, provide proof of timely notice to the employer. The state WC board will schedule a hearing. Appeals typically are processed within 30–90 days. If you disagree with the board's decision, further appeals may be available depending on state law.
Common Questions
What's the filing deadline for workers' comp claims?
Filing deadlines vary by state. Most states set deadlines through the state workers' compensation commission. There is no standard national deadline. Check your state's rules.
Why was my claim denied for not work-related?
Workers' comp covers only injuries occurring during employment. If the payer claims the injury is not work-related, appeal with documentation proving the injury occurred at work.
How do I appeal a workers' comp denial?
File appeals with your state workers' compensation board. Include proof of the work injury, medical documentation, and evidence of timely claim submission.
Altair checks workers' compensation requirements before submission . flagging missing authorizations and coding mismatches in real time. See how Altair works.
This reference is for informational purposes. Payer policies change frequently. Always verify against your state workers' compensation commission documentation. Last updated: 2026-03-16.