CO-27 Denial Code Explained

CO-27 is a medical billing denial code that indicates expenses were incurred after insurance coverage terminated. This denial commonly occurs when services are provided after the patient’s insurance policy became inactive.

What Does CO-27 Mean?

The CO-27 denial code means the insurance payer determined the patient’s coverage was no longer active on the date the medical service was performed.

This denial is often related to expired insurance plans, policy termination, or outdated eligibility information.

Common Reasons for CO-27

• Insurance coverage termination

• Expired patient insurance plans

• Incorrect eligibility verification

• Outdated insurance information

• Coverage inactive on service date

• Incorrect payer submission

How To Fix CO-27

Verify the patient’s active insurance coverage and confirm the correct payer information for the date of service. Providers may need to obtain updated insurance details, rebill another payer, or transfer financial responsibility to the patient if appropriate.

Eligibility verification before treatment can help reduce these denials.

Related Denial Codes

You may also encounter:

• CO-9 — Patient not eligible for benefits

• CO-170 — Coverage terminated before service date

• CO-22 — Coordination of benefits issue

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

Quick Summary

CO-27 indicates the patient’s insurance coverage had terminated before the service date. Most denials are caused by eligibility or inactive coverage issues.

Medical billing denial codes, insurance prefixes, and claim guidance in one searchable resource hub.

© 2026. All rights reserved.

Quick Links

Denial Codes

BCBS Prefixes

Articles

Resources

About ClariMed

Terms and Conditions

Privacy Policy