Billing for Physician Extenders

A physician extender is a licensed health care provider (not a physician) that provides medical services, typically performed by a physician. The term physician extender is commonly used to identify trained health care professionals such as physician assistants and nurse practitioners. Physician extenders typically work under the direct supervision of physicians.


Health plans are free to develop their own policies for credentialing and reimbursing physician extenders. Some health plans will credential the physician extender and some plans will not. Some plans follow Centers of Medicare and Medicaid (CMS) "incident to" guidelines and some plans do not. Therefore, it is important to contact each health plan to determine their policy regarding physician extenders. Below are a list of questions that the practice should ask the payer:

Do you credential physician extenders such as, nurse practitioners (NPs) and physician assistants (PAs)? Do you include them in your provider listing? Do you require any specific level of supervision? If the physician extender is not credentialed with the payer, then can the physician extender bill under the contracted supervising physician's billing numbers with the appropriate modifier? Confirm the appropriate modifier. Do you recognize and follow CMS "incident to"? What is the reimbursement rate for physician extenders if the service rendered is not "incident to"?


Physicians who bill Medicare for "incident to" will be reimbursed at 100% of the Medicare allowable. However, the following criteria must be met:

The physician has to have seen the patient at a previous visit and developed the plan of care that the physician extender will carry out.

The physician has to remained involved in the patient's care.

The physician extender has to be an expense to the physician/practice.

The physician must be physical present in the building.

The services must be provided in the office.

Important: If the patient is being seen by the physician extender for a different problem then this does not qualify as "incident to".

Have questions? I’m here to help.