Skip to main content

CO-B9 Denial Code: Patient Is Enrolled in Hospice

CO-B9 means the patient is enrolled in hospice, so the payer won't pay your claim separately. Services related to the terminal condition are generally the hospice's responsibility. Unrelated services, or services by an independent attending physician, may be payable with the right modifier.

Quick facts

Code
CO-B9 (CARC B9)
Status
Active In use since January 1, 1995; last modified September 30, 2007.
Code set
Claim Adjustment Reason Codes (CARC)
Group codes
  • CO (Contractual Obligation): The usual group. The provider can't bill the patient; the service is covered through the hospice benefit or must be rebilled correctly.
  • PR (Patient Responsibility): Rare. It may appear when the patient chose services outside the hospice plan of care after being informed of their liability.
Official description
Patient is enrolled in a Hospice.
X12 Claim Adjustment Reason Codes, retrieved September 25, 2026
Last verified
against the official X12 list.

What CO-B9 means

CARC B9 says the patient is enrolled in a hospice. When a patient elects hospice, the hospice becomes responsible for care related to the terminal illness and related conditions. Payers, including Medicare, generally stop paying other providers separately for that care. If your claim’s date of service falls inside a hospice election period, the payer may deny it with CO-B9.

Not every service during hospice is the hospice’s responsibility. Medicare Part B continues to pay for:

  • Services unrelated to the terminal condition, identified with modifier GW.
  • Services by the patient’s attending physician who is not employed by or paid under arrangement with the hospice, identified with modifier GV.

If your claim was for one of those and lacked the modifier, it’s likely to deny as a hospice service.

Common causes

  • Hospice election not known when the patient was scheduled or seen.
  • GW or GV modifier missing on a service that qualifies.
  • Related care billed directly instead of through an arrangement with the hospice.
  • Election dates in the payer’s system are wrong, or the patient revoked or was discharged from hospice before the service.
  • DME, labs, or drugs related to the terminal condition billed by outside suppliers.

How to fix it

  1. Run eligibility for the date of service and note the hospice election, revocation, or discharge dates.
  2. Decide whether the service relates to the terminal condition. Review the diagnosis and the hospice plan of care.
  3. If unrelated, add modifier GW (and supporting diagnosis) and send a corrected claim with resubmission code 7 in box 22.
  4. If you’re the independent attending physician, add modifier GV and resubmit.
  5. If related, contact the hospice. Payment typically comes from the hospice under an agreement, not from the payer.
  6. If the dates are wrong, ask the hospice or payer to correct them, then request reprocessing.

How to prevent it

  • Check eligibility for hospice election before every visit for seriously ill patients.
  • Coordinate with hospice agencies that serve your patients, including written arrangements for related services.
  • Train coders on GV and GW and the documentation each requires.
  • Flag hospice patients in your practice management system. See eligibility and COB denials.

Specialty notes

DME suppliers, labs, oncology practices, and home health agencies see CO-B9 most. Items and drugs used for symptom management of the terminal illness are generally part of the hospice’s responsibility.

Remark codes that may appear with CO-B9

  • N143 (The patient was not in a hospice program during all or part of the service dates billed.): The patient was not in a hospice program for all or part of the dates billed, useful when disputing overlapping dates.
  • MA94 (Did not enter the statement 'Attending physician not hospice employee' on the claim form to certify that the rendering physician is not an employee…): The claim didn't state that the attending physician is not a hospice employee.
  • CO-190 (Payment is included in the allowance for a Skilled Nursing Facility (SNF) qualified stay.): Payment is included in a skilled nursing facility stay, a similar 'covered elsewhere' situation.
  • OA-24 (Charges are covered under a capitation agreement/managed care plan.): Charges covered under a capitation or managed care arrangement.
  • CO-109 (Claim/service not covered by this payer/contractor.): Claim not covered by this payer; send it to the correct payer.
  • CO-B11 (The claim/service has been transferred to the proper payer/processor for processing.): The claim was transferred to the proper payer or processor.

CO-B9 FAQ

What modifiers apply to services for hospice patients?

For Medicare Part B, modifier GV identifies services by the patient's attending physician who is not employed by or paid under arrangement with the hospice. Modifier GW identifies services not related to the terminal condition. Use them only when documentation supports them.

Who pays for care related to the terminal diagnosis?

Under the Medicare hospice benefit, the hospice is responsible for care related to the terminal illness and related conditions. Other providers usually need an arrangement with the hospice to be paid for that care.

What if the patient revoked hospice?

Services after the revocation date are billed under regular benefits. Confirm the revocation date in the eligibility response and ask the payer to reprocess if the dates were wrong.

Can I bill the patient for CO-B9?

No. Under CO, don't bill the patient. Rebill correctly or seek payment from the hospice under your arrangement with it.