CO-37 Denial Code Explained

CO-37 is a medical billing denial code that indicates the claim was denied because the service is not covered under the patient’s current insurance contract. This denial commonly occurs when policy exclusions or payer limitations apply.

What Does CO-37 Mean?

The CO-37 denial code means the insurance payer determined the billed treatment or procedure is excluded from reimbursement under the patient’s policy agreement.

This denial is often related to policy exclusions or benefit restrictions.

Common Reasons for CO-37

• Non-covered procedures

• Policy exclusions

• Benefit limitations

• Out-of-network services

• Experimental treatments

• Incorrect payer billing

How To Fix CO-37

Review the patient’s insurance benefits and confirm whether the billed service is covered under the payer policy. Verify authorization requirements and payer guidelines before resubmitting or appealing the claim.

Providers may also need to discuss patient financial responsibility if coverage is unavailable.

Related Denial Codes

You may also encounter:

• PR-204 — Non-covered service denial

• CO-35 — Benefits unavailable under policy

• CO-96 — Non-covered service denial

• CO-109 — Coverage limitation denial

Quick Summary

CO-37 indicates the billed service is not covered under the patient’s insurance contract. Most denials are related to policy exclusions or benefit limitations.

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