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CO-164 - Denial Journal
CARC CO — Contractual Obligation

CO-164

Attachment/other documentation referenced on the claim was not received in a timely fashion

What This Code Means

The supporting documentation was received, but after the payer’s required deadline.

Common Causes

  • Documentation gathered and sent later than the payer's response window
  • Internal routing delay for medical records requests

How to Resolve or Appeal

  1. Track payer documentation deadlines closely once a request is received
  2. Appeal if there's a legitimate reason for the delay, with proof of when it was actually available

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

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