CO-29 Denial Code Explained

CO-29 is a medical billing denial code that indicates the time limit for filing the claim has expired. This denial commonly occurs when claims are submitted after the payer’s timely filing deadline.

What Does CO-29 Mean?

The CO-29 denial code means the insurance payer rejected the claim because it was not submitted within the allowed filing period established by the payer policy.

Timely filing limits vary by insurance company and plan type.

Common Reasons for CO-29

• Late claim submission

• Delayed billing processes

• Incorrect insurance information

• Claim resubmission delays

• Administrative processing issues

• Missed payer filing deadlines

How To Fix CO-29

Review the payer’s timely filing policy and confirm the original claim submission date. If documentation shows the claim was submitted on time, providers may submit an appeal with proof of timely filing.

Supporting documentation may include:

• Electronic claim confirmation reports

• Clearinghouse submission records

• Certified mailing receipts

• Payer acknowledgment records

Related Denial Codes

You may also encounter:

• CO-16 — Missing or incomplete claim information

• CO-18 — Duplicate claim submission

• CO-22 — Coordination of benefits issue

• PR-204 — Service not covered under patient benefit plan

Quick Summary

CO-29 indicates the claim exceeded the payer’s filing deadline. Most CO-29 denials are related to late claim submissions or missing timely filing documentation.

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