CO-34 Denial Code Explained

CO-34 is a medical billing denial code that indicates the patient and insured information submitted on the claim does not match payer records. This denial commonly occurs when demographic or policy information is incorrect.

What Does CO-34 Mean?

The CO-34 denial code means the insurance payer could not verify the patient or insured individual based on the submitted claim information.

This denial is often related to incorrect demographic details, invalid member information, or eligibility verification problems.

Common Reasons for CO-34

• Incorrect patient name

• Invalid member ID numbers

• Incorrect date of birth

• Mismatched insured information

• Incomplete insurance records

• Eligibility verification errors

How To Fix CO-34

Verify the patient’s demographic and insurance information before resubmitting the claim. Confirm member ID numbers, policy details, and insured information directly with the patient or payer.

Maintaining updated patient records can help reduce future denials.

Related Denial Codes

You may also encounter:

• CO-31 — Patient cannot be identified as insured

• CO-9 — Patient not eligible for benefits

• CO-30 — Patient not covered on date of service

• CO-32 — Patient not eligible for service benefits

Quick Summary

CO-34 indicates the patient or insured information submitted on the claim does not match payer records. Most denials are related to demographic or eligibility verification issues.

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