By: Albert R. Meyer, JD, MHA

Many clients come to me with questions regarding “incident to billing” of services and are dazed and and confused by having received a number of conflicting answers from various sources.  I’d like to take a moment to give an overview of the incident-to rules regarding MD supervision requirements for physician extenders (Nurse Practitioners, “CRNP” or Physician Assistants, “PA”).

It is highly recommend that physician extenders, providers and billing staff be trained on a regular basis on this subject.  Import points to take note of include:

  1. In order to bill a service “incident-to” a physician under the physician’s name and NPI number, the physician must perform the initial service. A PA, CRNP or other extender may not perform the initial service and have anything thereafter billed under the physician’s name, since there is nothing incident to the initial physician service.
  1. If a new patient exam is conducted by a PA or CRNP, those services are billable only under the PA and CRNP’s name and NPI number. There is nothing ever incident-to that patient for the course of care.
  1. If the physician performs the initial evaluation and management service, the physician must prepare a treatment plan. The PA or CRNP may implement the treatment plan with follow-up visits. The physician must maintain an active, ongoing involvement in the management of the patient’s condition throughout the course of the care in order to bill under the incident-to rule.
  1. If the preceding rules are satisfied, the physician must also provide direct, on-premises supervision. This requires the physician to be in the same medical suite, but not necessarily in the same office or room.
  1. The physician must at all times remain immediately available to intervene with the patient. This means the physician must be able to be interrupted. The physician cannot be performing some other procedure or task for which the physician is uninterruptable.
  1. If the patient has a new condition, the physician must see the patient for the new condition in order to bill subsequent visits performed by the PA or CRNP incident to the physician. If that does not happen, anything that flows from the new condition is not billable under the incident-to rule, but must be billed directly by the PA or CRNP.


  1. If all of the incident-to rules are not satisfied, the PA, CRNP or other extender must bill directly at the 85% of the Medicare Fee Physician Schedule, and may be applicable to commercial third party payor billing rules.


  1. More lenient state-based general supervision regulations do not apply to billing rules. Following state licensure regulations that allow for a supervising or collaborating physician to be away from the office suite will not comply with incent to billing and supervision requirements. This practice may result in False Claims Act liability.  While a PA or CRNP may treat patients during the absence f the physician in the office, Medicare must be billed under the PA’s provider number.  Most services performed by the PA may be billed “incident to” and billed under the physician’s provider number if the physician is physically present in the office at the time the services are provided.  CMS examines these situations very closely.  Therefore, it is crucial that you follow correct supervision and billing procedures based on the presence or absence of the supervising or collaborating physician.


Mr. Meyer is an attorney with over 20 years’ experience in health care law focusing on regulatory and transactional matters.  His clients include physicians, medical equipment companies, surgery centers and diagnostic centers.  Mr. Meyer works with clients nationwide in matters relating to Medicare regulations and compliance. He can be reached at 866-585-5444 or