CO-45 Denial Code
What it means
This isn't really a denial - it's the normal discount between the provider's full charge and the contracted rate. The provider writes off the difference.
Why it happens
The provider billed more than the insurer's contracted rate; the gap is a required write-off.
What to do
Usually nothing to appeal - you should not be billed the CO-45 amount. If a provider tries to bill you the difference (balance billing), that's often not allowed for in-network care.
Can you appeal it?
Rarely needed; flag if you're being balance-billed.
Official description
Charge exceeds the fee schedule / maximum allowable amount (contractual adjustment).
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