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CO-45 - Denial Journal
CARC CO — Contractual Obligation

CO-45

Charge exceeds fee schedule/maximum allowable or contracted amount

What This Code Means

The billed amount is more than the contracted or fee-schedule allowed amount; the difference is a contractual write-off, not something that can be billed to the patient.

Common Causes

  • Charges billed at standard rate rather than contracted rate
  • Fee schedule update not reflected in practice management system
  • Out-of-date contract terms loaded in billing software

How to Resolve or Appeal

  1. Confirm this is a standard contractual adjustment, not a payment error
  2. Write off the adjustment amount per the contract — do not bill the patient
  3. Periodically reconcile your fee schedule against current payer contracts
  4. Escalate to payer contracting if the allowed amount looks incorrect

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

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