Across the United States, physician assistants (PAs) continue to be vital members of the care team, expanding access to high-quality healthcare in settings ranging from primary care to specialty services. With more than 200,000 PAs in the United States and 20% employment growth projected between 2024 and 2034, the profession is projected to remain a core strategy in maintaining patient access in the years ahead.physician-assistants-employment-growth-2024-2034

As care delivery evolves and healthcare systems adapt to rising demand, PAs are exploring new ways to expand their impact on team-based care. Many are stepping into roles with greater autonomy, joining collaborative care teams, or choosing locum tenens jobs that offer greater flexibility and reach. For PAs considering new roles, understanding practice authority is an important part of the decision-making process.

Understanding Physician Assistant Practice Authority

PA practice authority varies significantly by state, with established levels of oversight or collaboration determined by state law, which often specifies whether a physician must be involved in care decisions, sign off on charts, or be physically present.

Some states have shifted toward allowing employers and care teams to determine these relationships based on the patient’s needs and the provider's experience. Others maintain legacy models that still require formal delegation or supervision. Understanding the spectrum is key for any PA considering where to practice.

What is the Scope of Practice by State for Physician Assistants?

To clarify the differences in the scope of practice for PAs, the American Academy of Physician Associates (AAPA) developed a four-tier model that categorizes each state’s regulatory environment:

  • Optimal: PAs are permitted to function at the full level of their education, clinical training, and experience. While collaboration, consultation, or referral may still occur, these decisions are based on the patient's needs, the PA's capabilities, and prevailing standards of care. In such environments, collaboration structures are typically determined by employers or healthcare teams rather than imposed by state law.
  • Advanced: PAs can practice to their full clinical capacity but are subject to additional administrative requirements imposed at the state level. These mandates, while not directly limiting scope, introduce operational complexity.
  • Moderate: The regulatory framework includes administrative constraints that affect how PAs and healthcare teams coordinate care. These requirements may limit the flexibility needed to optimize PA contributions in dynamic clinical environments.
  • Reduced: State policies restrict at least one component of PA practice. These limitations often reflect supervisory models that constrain the autonomy of both the PA and the broader care team, reducing responsiveness to evolving patient and system needs.

Where Are PAs Practicing with Greater Autonomy?

States continue to move along this spectrum as legislative efforts modernize existing policies. While “independent practice” is not the legal framework in most cases, many states are trending toward models that emphasize team-based flexibility over rigid oversight.

Seven states are categorized as having optimal PA scope-of-practice laws, including Iowa, Montana, New Hampshire, North Dakota, South Dakota, Wyoming, and Utah.

The map below provides a state-by-state snapshot of PA scope-of-practice environments, based on AAPA guidance:

PA State Practice Environment

  • =Optimal
  • =Advanced
  • =Moderate
  • =Reduced

Please note that this map provides a general overview of the scope of practice for physician assistants by state as of July 2025. State laws, regulations, and legislation are continually evolving, so individuals should consult state-specific sources for the most accurate and up-to-date practice information.

The Benefits of Working as a Locum Tenens Physician Assistant

For physician assistants evaluating where and how they want to practice, locum tenens offers a flexible way to explore different clinical and state practice environments. Rather than committing to a permanent role, PAs can pursue locum tenens jobs that align with their schedule, lifestyle, clinical interests, and long-term career goals.

Physician assistant locum tenens jobs can also provide exposure to a wide range of practice environments, including rural hospitals, outpatient clinics, specialty practices, and community health centers. Working across different clinical settings can help PAs broaden their experience, strengthen their adaptability, and identify the environments that best support their professional goals.

Partnering with a trusted locum tenens agency like Medicus can help simplify the process of working locum tenens physician assistant jobs. From licensing and credentialing to travel coordination and personalized job matching, the Medicus team supports physician assistants throughout each locum tenens job so they can focus on patient care and finding opportunities that fit their preferred practice environment.

The Future of Physician Assistant Care

As more states consider expanding the scope of practice and the need for accessible care continues to grow, PAs are helping shape a more responsive healthcare system. Whether working independently or as part of a care team, in permanent positions or through locum tenens, physician assistants remain vital to meeting rising demand for care.

Interested in working as a locum tenens physician assistant with Medicus? View our locum tenens physician assistant jobs here, or complete the short form below to connect with a Medicus recruiter.

Frequently Asked Questions About Physician Assistants’ Scope of Practice

Does Physician Assistant Scope of Practice Vary by State?

Yes. Physician assistant scope-of-practice laws are determined at the state level, meaning requirements for supervision, delegation, prescribing authority, and physician involvement differ significantly across the U.S. To learn more about physician assistants’ scope of practice, click here.

Can Physician Assistants Practice Independently?

In a growing number of states, yes—but the answer depends on how each state defines "independence." Most states do not use that term explicitly in legislation. Instead, they establish levels of oversight or collaboration, often specifying whether a physician must be involved in care decisions, sign off on charts, or be physically present.

How Many States Allow Physician Assistants to Have Optimal Practice?

According to the AAPA, seven states allow physician assistants to work under an optimal scope of practice.

What is the Difference Between Physician Assistant Supervision and Collaboration?

Supervision models typically require formal physician oversight, such as chart reviews or delegated authority agreements. Collaborative models are generally more flexible and focus on team-based care, allowing physicians and PAs to determine how they work together based on clinical needs and organizational policies.

Are Physician Assistant Scope of Practice Laws Changing?

Yes. Many states continue to modernize physician assistant practice laws to support team-based care and improve healthcare access amid ongoing physician shortages. Since requirements can change over time, PAs should consult state licensing boards or other official state-specific sources to confirm the current scope-of-practice laws in the states where they are interested in working.