CO-96 Denial Code: Non-Covered Charges

The official definition

“Non-covered charge(s)”

That is the verbatim definition of CARC 96 from the X12 Claim Adjustment Reason Code set, the standardized codes every insurer uses on EOBs and remittance advices. The letters in front of the number are the group code. CO: Contractual Obligation: an adjustment between the provider and the insurer. An in-network provider should not bill you for CO amounts.

What it means in plain English

The insurer says these charges aren't covered under your plan. On its own this code is vague. The accompanying remark code (RARC) carries the real reason. Sometimes the exclusion is genuine. Often enough, the service was misclassified (a medically necessary procedure coded as cosmetic, for example), and that's appealable.

What to check on your EOB

• The RARC code on the EOB. It states the specific reason for non-coverage.
• Your plan's Summary of Benefits and Coverage: is this service actually excluded?
• Whether the service could be misclassified. Reconstructive vs. cosmetic is the classic example.
• Whether ACA essential health benefit or state coverage mandates apply to this type of service.

What to do next

1. Verify the exclusion against your plan documents before accepting the denial.
2. If the service was misclassified, appeal with documentation showing the correct classification.
3. If the care was emergency or surprise out-of-network billing, check No Surprises Act protections.

Who's responsible

You (verify before paying). Most denials carry a clear owner. Knowing whether the fix belongs to you, your doctor, or the billing office is half the battle. If it's the provider's error, you should not be paying for it.

Want the fundamentals first? Start with how to read an EOB and the 7 most common billing errors. This page is general information about standardized denial codes, not legal or medical advice.