CMS 2026 Alert: Quarterly ICD-10-CM & NCCI updates active.
CO-146 - Denial Journal
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CO-146

Diagnosis was invalid for the date(s) of service reported

What This Code Means

The ICD-10 code submitted wasn’t a valid, billable code as of the date of service (codes update annually).

Common Causes

  • ICD-10 code retired or changed in the annual update
  • Code submitted was not yet effective on the date of service

How to Resolve or Appeal

  1. Check the ICD-10-CM code set effective for that specific date of service
  2. Correct and resubmit as a corrected claim

Educational reference only — not medical or legal advice. Always confirm code usage and appeal rights with the specific payer.

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