CO-96 denial code
Non-covered charges
How to fix it
Read the accompanying RARC. If exclusion is correct and a valid advance notice was issued, bill the patient; otherwise it is a write-off.
How to prevent it
Verify benefits for the specific service, not just active coverage, and issue advance notices where exclusion is likely.
In practice
A claim returns CO-96 — non-covered charges — accompanied by a remark code identifying the specific exclusion. Reading the remark code is the whole first step; CO-96 alone does not say why.
In this case the remark identifies a service excluded from the plan's benefit set. The exclusion is genuine and the service was performed knowing coverage was uncertain.
For a Medicare patient, whether the balance is billable turns entirely on whether a valid Advance Beneficiary Notice was signed before the service. With one, the balance transfers. Without one, it is written off — and the notice cannot be obtained after the fact.
What sits behind it
CO-96 and CO-50 are frequently confused. CO-50 is a medical necessity determination — the service might be covered for a different diagnosis. CO-96 is an exclusion — the service is not covered under this plan regardless of the clinical picture.
That distinction changes what an appeal can achieve. A necessity denial can be appealed with clinical documentation addressing the coverage criteria. An exclusion cannot be appealed on clinical grounds at all, because coverage was never available.
The prefix also matters more than the description here. CO-96 places the cost with the provider as a contractual obligation. The same non-covered situation carrying a PR prefix places it with the patient. Reading the prefix before deciding whether to bill is what prevents improper balance billing.
Related codes
Terms used here — Medical Necessity · Patient Responsibility · Appeal
How we handle it — Denial Management · Eligibility Verification · Patient Collections
Primary sources
The rules behind CO-96, at the bodies that publish them.
- Medicare Benefit Policy Manual (opens in a new tab)
Centers for Medicare & Medicaid Services — What Medicare covers and under what conditions, as distinct from how a claim is processed. The starting point for any coverage or medical necessity question.
- Advance Beneficiary Notice of Noncoverage (ABN) (opens in a new tab)
Centers for Medicare & Medicaid Services — The form and the rules for issuing it. Whether a non-covered service can be billed to the patient usually turns on whether a valid ABN was obtained beforehand.
- Medicare Coverage Database (LCD/NCD) (opens in a new tab)
Centers for Medicare & Medicaid Services — Searchable national and local coverage determinations. The direct answer to whether a diagnosis supports medical necessity for a given procedure.
Every denial code with a guide
Authorization
Bundling
Contractual
Coverage
Data quality
Documentation
Eligibility
Liability and workers comp
Patient responsibility
Provider eligibility
Timely filing
Looking for a different code? Search all 190 CARC and RARC codes
Questions about CO-96
CO-50 is a medical necessity determination — the service might be covered for a different diagnosis, so a clinical appeal is possible. CO-96 is an exclusion: the service is not covered under the plan regardless of the clinical picture, so there is nothing to appeal on clinical grounds.
For Medicare, only with a valid Advance Beneficiary Notice signed before the service, naming that service and the expected reason for denial. Without one it is written off, and the notice cannot be obtained retroactively. The CO prefix otherwise makes it a provider obligation.
Because CO-96 states only that charges are non-covered, not which exclusion applies. The accompanying remark code names the specific reason, and that determines whether anything can be done.
Verify benefits for the specific service rather than only confirming active coverage, and issue an advance notice where exclusion is likely. Eligibility confirms the patient is insured; benefits confirm whether this service is covered.
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