“Incident to” Office Guidelines

The CMS rules for billing office services as “incident to” a physician’s services are summarized within this document. Of note, the concept does not apply to services performed in the hospital environment, which includes inpatient, outpatient and emergency room hospital locations.

1. There are two ways in which office services may qualify for Incident to billing:
   
   Component services be performed by a clinical office employee of the physician or NPP who is the billing provider
   
   Employed clinical office staff may perform component functions as part of the billing provider’s service (e.g. administration of non-self-administrable drugs). The service must represent an integral part of the patient’s care and of a type commonly rendered in an office setting.
   
   Or
   
   Full services may be performed and billed incident to by Medicare-enrolled NPPs within a group practice that employs both Medicare-enrolled physicians and NPPs when incident to requirements are met
   
   In a group practice of Medicare-enrolled physicians and NPPs, a NPP may perform a service under direct physician supervision and the service may be billed under the physician’s NPI if all incident requirements are met. This rule applies to care for stable, established patients, for whom the NPP is following a plan of care originally developed by the physician and during which the physician is readily available in the office suite for any necessary supervision. When these requirements are not met, the NPP’s service must be billed with the NPP’s NPI.
    
2. Services must be medically reasonable and necessary and within the scope of Medicare coverage and the billing provider’s scope of practice:
   • Services not covered by Medicare (e.g., massage therapy or spiritual counseling) may not be included as part of a physician’s service.
   • Physicians may not bill services performed by non-Medicare enrolled physicians or NPPs.
   • Providers may not bill incident to services by employed providers whose scope of practice exceeds their own (e.g., a podiatry practice may employ a physician, but may not bill the physician’s services as incident to the podiatrist)
      
3. Incident to concepts apply only in the office setting (POS 11)
   • Exception: Home services for the homebound in medically underserved areas ‒ see the CMS IOM Publication 100-02, Medicare Benefit Policy Manual, Chapter 15, Section 60.4B (1 MB).
   • The term “Clinic” only applies as defined as a physician owned and operated clinic, where providers work together in a large office. The concept does not apply to hospital or other facility-based clinics.
      
4. The incident to service must be integral although incidental
   • When services are performed by employees of the provider, they must be an integral part of the provider’s overall plan of care and essential to the patient’s course of treatment (e.g., obtaining vital signs or administering an injection on the provider’s behalf).
   • When a service is performed by a clinical employee without physician participation (e.g., a nurse sees the patient for a blood pressure check or review of medication), the service may be billed by the physician as CPT 99211, as long as the physician is present in the office suite during the service and all incident to requirements are met.
      
5. Incident to billing does not apply to new patients or established patients who present with new problems.
   • As with all E/M services, the rendering provider must confirm the history of the present illness (HPI) from the patient since this requires clinical skill. When the HPI reveals a new problem(s), the visit cannot be billed incident to by the NPP since it may require changes to the physician’s original plan of care. This visit can be performed and billed by either the physician or the NPP, but cannot be billed by the NPP using the physician’s NPI.
   •  Services to new patients or established patients who present with new problems must be billed using the NPI of the provider who sees the patient that day. This means that such patients may be seen by either a physician or NPP within a practice, but that the service can only be billed under the physician’s NPI when the physician actually sees the patient. NPPs who see patients in these circumstances must bill the service as performed by an NPP.
      
6. Services to established patients with no new problems may be provided by NPPs and billed under the NPI of the supervising physician, as long as the physician is immediately available in the office suite and the NPP is following the plan of care set forth by the physician on the initial visit.
   • The record must reflect an initial physician visit and periodic review and oversight by the physician of his/her initial plan of care as administered by the NPP.
   • Visits with established patients who are experiencing new problems require active physician participation and cannot be billed on an incident to basis.
   • For all patients, it is expected that the physician performs and documents intermittent, subsequent services of a frequency that reflects active participation of the course of treatment for the specific problem.
      
7. Incident to billing for visits including medication adjustment(s)
   • A physician’s initial plan of care may include prescription medication that may require adjustment on subsequent visits; the need for medication adjustment does not represent a “new problem.” These visits may be billed by an NPP as incident to the original plan of care when the physician includes that instruction in the original plan. An example: “Have started patient on Losartan 100 mg. po qd for BP 160/90; patient to RTO in two weeks for f/u. Dosage may be adjusted by NP on f/u visits.”
      
8. Direct Supervision by a physician is required.
   • Incident to billing requires direct supervision by the supervising physician who must be present in the office suite and immediately available and able to provide assistance and direction throughout the time the service is performed.
   • The supervising physician does not have to be in the same room but must be in the office or clinic suite.
   •  For group practices, any physician member of the group may provide supervision to NPPs under this guideline.
      
9. Documentation
   • Documentation must support evidence that a supervising physician was present and available. The documentation submitted to support billing “incident to” services must clearly link the services of the NPP staff to the services of the supervising physician(s). Evidence of the link may include:
   • • While cosignature of the supervising physician is not required, it is suggested as a means of verifying the physician’s availability for oversight.
     • The NPP performing the service may include entry in the note of the identity and credentials of the supervising physician who was available during the visit.
     • Documentation from other dates of service, both initial and subsequent, should clearly establish a link between the two providers.

Reviewed 10/10/2023