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CO-183 - Denial Journal
CARC CO — Contractual Obligation

CO-183

The referring provider is not eligible to refer the service billed

What This Code Means

The payer’s records show the referring provider isn’t eligible/enrolled to make referrals for this type of service.

Common Causes

  • Referring provider not enrolled with the payer
  • Referring provider's NPI entered incorrectly

How to Resolve or Appeal

  1. Verify the referring provider's enrollment status with the payer
  2. Correct the referring provider information and resubmit

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

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