CO-66 Denial Code Explained
CO-66 is a medical billing denial code that indicates the claim was denied because the procedure or treatment did not meet payer coverage guidelines or reimbursement requirements.
DENIAL CODE
3/7/20221 min read
CO-66 Denial Code Explained
CO-66 is a medical billing denial code that indicates the claim was denied because the procedure or treatment did not meet payer coverage guidelines or reimbursement requirements.
What Does CO-66 Mean?
The CO-66 denial code means the insurance payer determined the billed service failed to qualify for reimbursement under current coverage policies.
This denial is often related to documentation deficiencies or payer medical policy limitations.
Common Reasons for CO-66
Failure to meet payer guidelines
Insufficient documentation
Unsupported diagnosis information
Medical necessity concerns
Incorrect coding combinations
Missing treatment records
How To Fix CO-66
Review payer coverage policies and confirm all clinical documentation supports the billed treatment. Providers may need to submit additional records or corrected coding information before resubmitting the claim.
Related Denial Codes
You may also encounter:
Quick Summary
CO-66 indicates the payer determined the billed treatment did not qualify for reimbursement under current coverage policies. Most denials are related to documentation or medical necessity concerns.
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