The 10 most common denial codes and what each one actually means
A denial code is a diagnosis, not a verdict. Here is what the ten you will see most often are really telling you, and what the fix is for each.
Category
Denials & Appeals
CARC codes, appeal strategy, and the prevention work that stops denials recurring.
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How to appeal a medical necessity denial (CO-50)
CO-50 is a coverage policy decision, not a coding error — which means it is appealable, and a well-structured appeal wins far more often than practices expect.
CO-197: what a prior authorisation denial really costs
Most denials are recoverable. CO-197 frequently is not — and in many contracts you cannot bill the patient either. That makes it the most expensive denial category there is.