Not legal advice - Denial Decoder helps you understand insurance denials; it doesn't replace a licensed attorney, doctor, or patient advocate.

Denial Decoder
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CO group

CO-204 Denial Code

What it means

The item simply isn't a covered benefit under your specific plan.

Why it happens

The service/drug/device is excluded from your plan's benefits.

What to do

Check your Summary of Benefits. If it should be covered (or is required by a mandate), appeal. If truly excluded, ask about a formulary exception or alternative covered option.

Can you appeal it?

Sometimes - via exception or mandate argument.

Official description

This service/equipment/drug is not covered under the patient's current benefit plan.

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