Advanced Practice Registered Nurses (APRNs)

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For information on how to enroll in Medicare, visit Advanced Practice Nonphysician Practitioners.  

Certified Registered Nurse Anesthetists (CRNAs)

Qualifications & Criteria

You must:

Service Requirements

You must meet these requirements:

  • You’re legally authorized to perform anesthesia and related care in the state where you provide the services.
  • Unless the state where you practice opted out of Medicare supervision requirements, you must:

    • In a hospital, you must be under the operating practitioner’s supervision or that of an anesthesiologist who’s immediately available, if needed. Immediate supervision means an anesthesiologist is physically located within the same area as the certified registered nurse anesthetist (CRNA) and can provide immediate hands-on intervention.

    • In a critical access hospital (CAH) or ambulatory surgical center (ASC), you must be under the operating practitioner’s supervision.

Billing Guidelines

  • You may bill for your services using:
    • Your NPI
    • The hospital, physician, group practice, or ASC NPI where you have an employment or contractual relationship
  • Anesthesia time is the continuous period that:
    • Begins when you’ve prepared the patient for anesthesia services in the operating room or equivalent area
    • Ends when you place the patient safely under post-operative care
  • You may add blocks of anesthesia time if you furnish continuous anesthesia care within the time periods around an interruption
  • Anesthesia billing modifiers include:

    • QS: Monitored anesthesia care service

      Note:
      A physician or a qualified non-physician anesthetist may use the QS modifier for informational purposes. You must report actual anesthesia time and 1 payment modifier on the claim.
    • QX: CRNA service: with medical direction by a physician
    • QY: Medical direction of 1 certified registered nurse anesthetist (CRNA) by an anesthesiologist
      • Note: Used by a supervising physician. 
    • QZ: CRNA service without medical direction by a physician

Payment Guidelines

  • We pay only on an assignment basis
  • We pay services at 100% under the Physician Fee Schedule (PFS) or in accordance with the level of supervision provided
  • Under the Anesthesia Fee Schedule based on applicable locality adjusted anesthesia Conversion Factor (CF) multiplied by the sum of allowable base and time units; 1 anesthesia time unit = 15 minutes anesthesia time
  • The patient may be responsible for paying you for a Part B copayment, deductible, or coinsurance
  • We may pay you directly or pay another individual or entity where you have an employment or contractual arrangement

More Information

Nurse Practitioners (NPs)

Qualifications & Criteria

For Part B coverage of nurse practitioner (NP) services, you must be a licensed registered professional nurse authorized by the state where you provide NP services according to state law and meet 1 of these requirements:

  • Got Medicare billing privileges for the first time on or after January 1, 2003, and:
    • Are NP certified by a recognized national certifying body (PDF) with established NP standards
    • Have a master’s degree in nursing or a Doctor of Nursing Practice (DNP) doctoral degree
  • Got Medicare NP-billing privileges the first time before January 1, 2003, and are NP-certified by a recognized national certifying body (PDF) with established NP standards
  • Got Medicare NP-billing privileges the first time before January 1, 2001

For Medicare coverage of NP services in a CAH, you must be a licensed registered nurse (RN) authorized by the state where you provide NP services according to state law and meet 1 of these requirements:

  • Are a primary care NP certified by the American Nurses’ Association or by the National Board of Pediatric Nurse Practitioners and Associates
  • Successfully completed a 1-year program that:
    • Prepares RNs to perform an expanded role in the delivery of primary care
    • Includes at least 4 months of classroom instruction and a component of supervised clinical practice
    • Awards a degree, diploma, or certificate to people who successfully complete the program
  • Successfully completed a formal education program for preparing RNs to perform an expanded role in delivering primary care that doesn’t meet the clinical nursing degree program requirements and has been performing an expanded role in delivering primary care for a total of 12 months during the 18-month period immediately preceding June 25, 1993

Service Requirements

You must meet these requirements:

  • You’re legally authorized to practice medicine in the state where you work.
  • The services are reasonable and necessary.

  • The services are what we consider physician services as if a doctor of medicine (MD) or doctor of osteopathy (DO) provided them. Physician services are professional patient services a physician performs, including diagnosis, therapy, minor surgery, consultation, and care plan oversight.

  • You provide your professional services in collaboration with a physician. Collaboration happens when NPs work with 1 or more physicians to deliver health care services within their professional scope of expertise with medical direction and appropriate supervision as required by state law.

Additional service requirements apply for NPs working in a CAH.

Coverage & Documentation Guidelines

  • We may cover assistant-at-surgery services you personally provide.

  • You may have services and supplies provided incident to your personal professional services.

  • You may certify patient eligibility under the Medicare home health benefit and oversee their plan of care. You may bill HCPCS codes G0179, G0180, and G0181.

  • You may review and verify (sign and date), rather than re-document, notes in a patient’s medical record, including documentation of your presence and service participation, made by:

    • Physicians

    • Residents

    • Nurses

    • Medical, physician assistant, or advanced practice registered nurse students

    • Other medical team members

Billing Guidelines

  • You may:
    • Use your NPI to bill your services
    • Let an employer or contractor use your NPI to bill your reassigned
  • To bill for incident to services:
    • Use your NPI if you’re a non-physician practitioner (NPP)
    • If you provide services incident to another physician’s or nonphysician practitioner’s services, the supervising physician or nonphysician practitioner must use their NPI to bill the incident to professional services you provide
  • Report only modifier AS on the claim when you bill assistant-at-surgery services.
  • We apply reasonable and necessary standards to each billing request. This limits our payments to covered services that address and treat patient complaints and symptoms. Services must meet specific medical necessity statutes, regulations, manual requirements, and National Coverage Determinations (NCDs) and Local Coverage Determinations (LCDs). For each billed service, note specific signs, symptoms, or patient complaints that make each service reasonable and necessary.

Payment Guidelines

  • We pay only on an assignment basis.
  • You can’t charge a patient more than the amounts permitted under 42 CFR 424.55. If a patient pays more for a service than the assignment payment limits, you must refund the excess amount.

  • We pay services at 80% of the lesser of the actual charge or 85% of the amount a physician gets under the PFS when provided outside a hospital or skilled nursing facility (SNF) setting.

  • We pay you directly for assistant-at-surgery services at 85% of 16% of the amount a physician gets under the PFS.
  • We pay you for “incident to” services provided by auxiliary personnel (outside a hospital or SNF setting) at 85% of the amount a physician gets under the PFS.
  • We pay your professional services only when:
    • You personally perform the services.
    • There aren't any facility or other provider charges. 

More Information

Clinical Nurse Specialists (CNSs)

Qualifications & Criteria

You must:

  • Be an RN currently licensed in the state where you practice and be authorized to provide clinical nurse specialist (CNS) services according to state law
  • Have a DNP or master’s degree in a defined clinical nursing area from an accredited educational institution
  • Be CNS-certified by a recognized national certifying body (PDF) with established CNS standards

Service Requirements

You must meet these requirements:

  • You’re legally authorized to practice medicine in the state where you provide the services.
  • The services are reasonable and necessary.
  • The services are what we consider the physician services as if an MD or DO provided them. Physician services are professional patient services a physician performs, including diagnosis, therapy, surgery, consultation, and care plan oversight.
  • You provide your professional services in collaboration, which happens when CNSs work with 1 or more physicians to deliver health care services within their professional scope of expertise and provide medical direction and appropriate supervision required by state law where they perform services.

Coverage & Documentation Guidelines

  • We may cover assistant-at-surgery you personally provide.

  • You may have services and supplies provided incident to your personal professional services.

  • You may certify patient-eligibility under the Medicare home health benefit and oversee their plan of care. You may bill HCPCS codes G0179, G0180, and G0181.
  • You may review and verify (sign and date), rather than re-document, notes in a patient’s medical record made by:
    • Physicians
    • Residents
    • Nurses
    • Medical, PA, or APRN students
    • Other medical team members

Billing Guidelines

  • You may:
    • Use your NPI to bill your services
    • Let an employer or contractor use your NPI to bill your reassigned services
  • To bill for incident to services:
    • Use your NPI, if you’re an NPP.
    • If you provide services incident to a physician’s or NPP’s services, the supervising physician or NPP must use their NPI to bill the incident to professional services you provide.
  • Report only the modifier AS on the claim when you bill assistant-at-surgery services.
  • We apply reasonable and necessary standards to each service you bill. This limits our payments to covered services that address and treat patient complaints and symptoms. Services must meet specific medical necessity statutes, regulations, manual requirements, NCDs, and LCDs. For each billed service, note specific signs, symptoms, or patient complaints that make each service reasonable and necessary.

Payment Guidelines

  • We pay only on an assignment basis.
  • You can’t charge a patient more than the amounts permitted under 42 CFR 424.55. If a patient pays more for a service than the assignment payment limits, you must refund the excess amount.
  • We pay your personal professional services at 80% of the lesser of the actual charge or 85% of the amount a physician gets under the PFS when provided outside a hospital or SNF setting.
  • We pay you directly for assistant-at-surgery services at 85% of 16% of the amount a physician gets under the PFS.
  • We pay your incident to services provided outside a hospital or SNF setting at 85% of the amount a physician gets under the PFS.
  • When you bill your services in the hospital setting (inpatient and outpatient), we unbundle the payment and make the payment directly to you under the PFS.
  • We pay your professional services only when:
    • You personally perform the services.
    • There aren't any facility or other provider charges. We don’t pay any amount to other professionals for providing services.

More Information

Certified Nurse-Midwives (CNMs)

Qualifications & Criteria

You must:

  • Be an RN legally authorized to practice in the state where you provide services
  • Have successfully completed a nurse-midwives study and clinical experience program accredited by an approved U.S. Department of Education accrediting body
  • Be certified as a nurse-midwife by the American College of Nurse-Midwives or the American College of Nurse-Midwives Certification Council

Service Requirements

You must meet these requirements:

  • The services are reasonable and necessary
  • Services are within the scope of practice authorized by the state where they’re provided and we would otherwise cover them if provided by a physician or as incident to a physician’s service
    • We consider the services physician services if a MD or DO provided them
    • Physician services are professional patient services a physician performs, including diagnosis, therapy, minor surgery, consultation, and care plan oversight
  • You provide services without physician supervision and without association with a physician or other health care provider, unless otherwise required under state law

Coverage & Documentation Guidelines

  • You may have services and supplies provided incident to your personal professional services
  • We cover services in all settings, including:
    • Birthing centers
    • Clinics
    • Hospitals
    • Certified nurse-midwife (CNM) offices
    • Patients’ homes
  • You may review and verify (sign and date), rather than re-document, notes in a patient’s medical record made by:
    • Physicians
    • Residents
    • Nurses
    • Medical, physician assistant, or advanced practice registered nurse students 
    • Other medical team members

These notes can include information documenting your presence and service participation.

Billing Guidelines

  • You may:
    • Use your NPI and specialty code 42 to bill your services
    • Let an employer or contractor use your NPI and specialty code 42 to bill your reassigned services
  • To bill for incident to services:
    • Use your NPI, if you’re a supervising physician or NPP
    • If you provide services incident to another physician’s or NPP's services, the supervising physician or NPP must use their NPI to bill the incident to professional services you provide

Payment Guidelines

  • We pay only on an assignment basis.
  • You can’t charge a patient more than the amounts permitted under 42 CFR 424.55. If a patient pays more for a service than the assignment payment limits, you must refund the excess amount.
  • We pay services at 80% of the lesser of the actual charge or 100% of the amount a physician gets under the PFS.
  • We pay covered drugs and biologicals provided incident to your services according to Part B drug and biological payment methodology.
  • We pay your incident to services provided outside a hospital or SNF setting at 100% of the amount a physician gets under the PFS.
  • We pay your covered clinical diagnostic lab services according to the clinical lab fee schedule.
  • When you bill directly for services in the hospital setting (inpatient and outpatient), we unbundle the payment and make the payment to you under the PFS.
  • When you provide most of a global service and call in a physician to provide a portion of the care or when the physician provides most of the service and calls you in, we base payment on the portion of the global fee that we would pay to the billing practitioner. You and physicians use reduced service modifiers to report that they didn’t provide all covered global allowance services.

More Information

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Page Last Modified:
04/17/2026 12:18 PM
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