CO-51Contractual Adjustment
Not medically necessary -- quantity exceeds plan limits
What this code means
The insurer approved this service but says you received more units or visits than your plan covers. The excess amount is being denied.
What to do next
Review your plan documents for visit or unit limits. If you believe the quantity was clinically necessary, appeal with documentation from your treating physician. Some limits can be exceeded with medical necessity documentation.
Appeal outlook: Moderate with strong clinical documentation
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