Healthcare Error Code
Healthcare Insurance / Medical Billing
Claim Adjustment Reason Codes (CARC)

CO-39 | Services denied as experimental

Industry
Healthcare
Canonical
/healthcare/error-codes/co-39/
Last Updated
Feb 25, 2026
Summary

This code indicates that the payer considers the service experimental or investigational under the plan.

Advertisement after-summary
Ad Space

What This Code Means

CO-39 is used when a payer determines that a service does not meet coverage criteria due to its experimental or investigational status. Coverage policies define which services qualify for reimbursement. This determination is based on policy guidelines rather than claim submission quality. It does not imply improper billing or service delivery. Coverage decisions may differ between payers.

Where Users Usually See This Code

  • EOB statements
  • Remittance advice
  • Coverage determination notices

Why This Code Appears

  • The service is classified as experimental by the payer
  • Coverage criteria were not met
  • Policy guidelines restrict reimbursement

What Typically Happens Next

  • The service is denied for payment
  • The claim is closed
  • Appeal options may exist depending on policy

What This Code Is Not

  • It is not a documentation error
  • It is not a contractual adjustment
  • It is not an automatic audit trigger

Troubleshooting Checklist

  • Review coverage policy language
  • Confirm classification criteria
  • Monitor policy updates

Notes And Edge Cases

Definitions of experimental services vary by insurer. Policy updates may change how this code is applied over time.

Related Codes

8 links
Advertisement near-bottom
Ad Space
ErrorCodesIndex logo