CO-170 Denial Code Explained

CO-170 is a medical billing denial code that indicates payment is denied because the service was performed after the patient’s insurance coverage terminated. This denial commonly occurs when eligibility information is outdated or coverage verification was incomplete.

What Does CO-170 Mean?

The CO-170 denial code means the insurance payer determined the patient was not actively covered under the insurance plan on the date of service.

This denial is often related to terminated policies, incorrect eligibility records, or inactive insurance coverage.

Common Reasons for CO-170

• Expired insurance coverage

• Incorrect eligibility verification

• Outdated insurance information

• Coverage terminated before service date

• Incorrect policy effective dates

• Patient plan cancellation

How To Fix CO-170

Verify the patient’s insurance eligibility and confirm active coverage for the date of service. Providers may need to obtain updated insurance information, rebill the correct payer, or discuss payment responsibility with the patient.

Eligibility checks before treatment can help reduce future denials.

Related Denial Codes

You may also encounter:

• CO-22 — Coordination of benefits issue

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

• CO-29 — Timely filing denial

• CO-16 — Missing or incomplete claim information

Quick Summary

CO-170 indicates the patient’s insurance coverage was inactive on the date of service. Most denials are caused by eligibility verification or coverage termination issues.

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