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CO-280 Denial Code: Medical Plan Denied, Bill Pharmacy Plan

CO-280 means the medical plan received the claim but benefits aren't available under it; submit the services to the patient's pharmacy plan. It usually involves drugs or supplies the plan covers only through the pharmacy benefit. The medical plan didn't forward the claim.

Quick facts

Code
CO-280 (CARC 280)
Status
Active In use since March 1, 2017; last modified November 1, 2017.
Code set
Claim Adjustment Reason Codes (CARC)
Group codes
  • CO (Contractual Obligation): The usual group. The provider should redirect the service to the pharmacy benefit; the patient isn't billed on the medical denial.
  • PR (Patient Responsibility): Sometimes used when the payer assigns the amount to the patient. Check pharmacy coverage options before billing.
Official description
Claim received by the medical plan, but benefits not available under this plan. Submit these services to the patient's Pharmacy plan for further consideration.
X12 Claim Adjustment Reason Codes, retrieved September 25, 2026
Last verified
against the official X12 list.

What CO-280 means

CARC 280 says the claim was received by the medical plan, but benefits aren’t available under this plan; submit these services to the patient’s pharmacy plan. The medical plan considers the item a pharmacy benefit. X12 notes that if the medical plan forwards the claim to the pharmacy plan, payers should use CARC 292 instead, so CO-280 means you need to act.

Health plans divide drugs between the medical benefit and the pharmacy benefit. Drugs administered in an office or facility are often medical benefits, billed with HCPCS codes on a medical claim. Self-administered drugs and some specialty drugs are often pharmacy benefits, processed through a pharmacy benefit manager. The split varies by plan, and some plans move specific drugs from the medical benefit to the pharmacy benefit, requiring them to be obtained through a specialty pharmacy.

Common causes

  • Self-administered drugs billed on a medical claim.
  • Specialty drugs the plan requires through a designated pharmacy.
  • Supplies, such as diabetic testing supplies, covered under pharmacy for some plans.
  • Vaccines covered under the pharmacy benefit for certain plans.
  • Plan benefit changes moving a drug from medical to pharmacy coverage.

How to fix it

  1. Confirm the plan’s benefit rules for the drug or supply.
  2. Coordinate with the pharmacy benefit or its specialty pharmacy for future doses, typically through a prescription.
  3. For the denied service, ask the payer about exceptions, a medical benefit review, or whether a pharmacy claim can be submitted.
  4. Rebill the administration service separately if it’s still covered under the medical benefit.
  5. Bill the patient only when allowed under the plan and your agreements.

How to prevent it

  • Check medical versus pharmacy coverage before buying and administering drugs.
  • Verify benefits for specialty drugs at each plan year.
  • Use specialty pharmacy workflows for drugs the plan requires through pharmacy.
  • Flag drug codes by payer benefit. A Claims Validator can warn when a drug is billed to a medical plan that covers it only through pharmacy.

Specialty notes

Oncology, rheumatology, neurology, and endocrinology practices that administer injectable or infused drugs see CO-280 most, particularly with plans that manage specialty drugs through the pharmacy benefit.

Remark codes that may appear with CO-280

  • N130 (Consult plan benefit documents/guidelines for information about restrictions for this service.): Points to plan documents describing which drugs are covered under the pharmacy benefit.
  • CO-292 (Claim received by the medical plan, but benefits not available under this plan.): The same situation, but the medical plan forwarded the claim to the pharmacy plan.
  • CO-270 (Claim received by the medical plan, but benefits not available under this plan.): Medical plan says to bill the dental plan instead.
  • CO-109 (Claim/service not covered by this payer/contractor.): Not covered by this payer; send to the correct payer.
  • CO-96 (Non-covered charge(s).): General non-covered charge, used with remark codes.

CO-280 FAQ

Why would a drug be covered only under the pharmacy benefit?

Plans decide whether each drug is a medical benefit (billed by the provider who administers it) or a pharmacy benefit (dispensed by a pharmacy). Many self-administered drugs, and some specialty drugs, are pharmacy benefits only.

What's the difference between CO-280 and CO-292?

With CO-280, you must redirect the service to the pharmacy plan yourself. With CO-292, the medical plan forwarded the claim to the pharmacy plan.

Can a physician's office bill the pharmacy benefit?

Usually not directly. Offices often have the drug dispensed by a specialty pharmacy under the patient's pharmacy benefit and delivered for administration. Some plans allow other arrangements; check the plan's rules.

What if the drug was already given?

Ask the payer whether an exception or medical benefit review is possible. If not, review your financial agreements with the patient and the plan's rules before billing.