Washington collaborating physician requirements differ from most other states in one significant way. Washington is a full practice authority state for Advanced Registered Nurse Practitioners. ARNPs in Washington can diagnose, treat, and prescribe medications, including controlled substances, without a physician agreement, under the sole licensure authority of the Washington State Board of Nursing. That classification changes the demand picture for physician collaboration in Washington but does not eliminate it.
For physicians exploring collaboration roles in Washington, the relevant framework centers on physician assistants. PAs in Washington are still required to enter into a written collaboration or supervision agreement with a participating physician before commencing practice. That agreement governs the PA’s scope, the oversight structure, and the physician’s responsibilities throughout the arrangement. This guide covers every requirement a physician needs to understand in 2026.
Washington Collaborating Physician Overview: Where Washington Stands
Washington grants full practice authority to ARNPs under WAC 246-840-300 and RCW 18.79.250. As a licensed independent practitioner, an ARNP provides a wide range of health care services including the diagnosis and management of acute, chronic, and complex health conditions without physician oversight or a collaborative agreement. This is not a transition-period arrangement. There is no minimum hour requirement and no application needed before an ARNP can practice independently in Washington.
For physician assistants, the framework is different. Washington enacted HB 2041 in 2024, which took effect January 1, 2025, and replaced the older supervision-only model with a tiered approach. Experienced PAs now move from a supervision requirement into a collaboration model once they meet defined hour thresholds. Less experienced PAs remain under physician supervision. Both tiers require a written agreement with a participating physician before practice begins.
Governing Body
The Washington Medical Commission governs physician licensure, the collaboration agreement framework for PAs, and disciplinary matters under RCW 18.71A.
NP Practice Authority in Washington: What Full Practice Means for Physicians
Because ARNPs in Washington do not require physician agreements by law, the traditional clinic model built around a physician delegating prescriptive authority to an NP does not apply here. Clinics operated by ARNPs in Washington are legally compliant without any physician involvement at the clinical oversight level.
That said, full practice authority under state law does not override employer or credentialing policies at health systems, hospitals, or specialty practices. Many facilities in Washington continue to structure collaborative relationships internally, and some clinic models voluntarily involve physician oversight for clinical reasons that go beyond regulatory compliance. These arrangements are contractual rather than statutory.
For physicians seeking supplemental income through collaboration roles in Washington, the primary regulatory pathway is through PA collaboration agreements, not NP oversight arrangements.
Where Physician Collaboration Still Applies in Washington
Physician collaboration in Washington is active and required in several real-world contexts:
- All PA arrangements. Every PA licensed in Washington must have a written collaboration or supervision agreement with a participating physician before commencing practice, regardless of experience level.
- PA specialty transitions. A PA with 4,000 or more hours of postgraduate experience who changes specialties must complete an additional 2,000 supervised hours in the new specialty before moving to a collaborative model in that area.
- Employer or facility policies. Some health systems and clinic operators require physician collaboration even for ARNPs as an internal standard, independent of state law.
- Voluntary collaboration. Some ARNP-operated clinics choose to formalize physician involvement for clinical support, liability structuring, or service-specific reasons.
For the purposes of this guide, the compliance requirements and physician obligations described below apply to PA collaboration arrangements, which represent the primary statutory collaboration framework in Washington.
The Collaboration Agreement: Washington’s Core Compliance Document for PAs
Washington uses the term collaboration agreement, as defined under RCW 18.71A.120. This is the written document that must be in place before a PA commences practice. The agreement defines the duties and responsibilities of both the PA and the participating physician, the scope of services the PA is authorized to provide, and the oversight structure that applies based on the PA’s postgraduate clinical practice hours.
Under RCW 18.71A.120(1)(a), prior to commencing practice, a physician assistant licensed in Washington state must enter into a collaboration agreement that identifies at least one participating physician and that is signed by one or more participating physicians or the physician assistant’s employer.
The collaboration agreement must be available either electronically or on paper at the PA’s primary location of practice and made available to the Washington Medical Commission upon request. There is no state board filing requirement for PA collaboration agreements in Washington. The agreement is maintained at the practice site, not submitted to a central registry.
Entering into a collaboration agreement is voluntary for the participating physician. Under RCW 18.71A.120(1)(c), a physician may not be compelled to participate in a collaboration agreement as a condition of employment.
What Must Be in a Washington Collaboration Agreement
Washington law specifies the minimum required content of a valid collaboration agreement under RCW 18.71A.120(2). The agreement must include all of the following:
1. Duties and Responsibilities of Both Parties
The agreement must describe the duties and responsibilities of the PA and the participating physician or physicians. It must also describe the supervision or collaboration requirements for specified procedures or areas of practice, depending on the number of postgraduate clinical practice hours the PA has completed.
2. Scope of Practice Statement
The acts, tasks, or functions included in the agreement must be within the scope of expertise and clinical practice of either the participating physician, the group of physicians in the relevant department, or the specialty areas in which the PA is practicing. The collaboration agreement may only include acts, tasks, or functions that the PA is qualified to perform by education, training, or experience.
3. Communication and Availability Process
The agreement must describe a process between the PA and the participating physician or physicians for communication, availability, and decision making when providing medical treatment to a patient, including in the event of an acute health care crisis not previously covered by the agreement.
4. Backup Physician Protocol
If there is only one participating physician identified in the collaboration agreement, the agreement must include a protocol for designating another participating physician for consultation in situations in which that physician is not available.
5. Hour Attestation and Termination Provision
The agreement must include an attestation by the PA of the number of postgraduate clinical practice hours completed, including hours completed in any chosen specialty. It must also include a termination provision.
6. Credential Verification
Before entering into the collaboration agreement, the participating physician, employer, or their designee must verify the PA’s credentials.
Supervision vs. Collaboration: The Hours Threshold That Changes Everything
Washington’s PA framework under RCW 18.71A.030 creates two distinct tiers of physician oversight depending on the PA’s postgraduate clinical practice experience. This is one of the most practically significant features of the Washington model.
Tier 1: Supervision (Fewer Than 4,000 Hours)
A PA who has completed fewer than 4,000 hours of postgraduate clinical practice must work under the supervision of a participating physician. Supervision is described in the collaboration agreement and determined at the practice site. Supervision does not require the personal physical presence of the participating physician at the place where services are rendered, but the physician must be accessible and involved in the oversight structure defined in the agreement.
Tier 2: Collaboration (4,000 or More Hours, Plus 2,000 Specialty Hours)
A PA with 4,000 or more hours of postgraduate clinical practice may work in collaboration with a participating physician, provided the PA has also completed 2,000 or more supervised hours in the PA’s chosen specialty. In the collaboration model, the PA interacts with, consults with, or refers to a physician or other appropriate members of the health care team as indicated by the patient’s condition, the PA’s education and experience, and the standard of care. The degree of collaboration is determined by the practice, which may include decisions made by the PA’s employer, group, hospital service, and credentialing and privileging systems of licensed facilities.
Specialty Changes After 4,000 Hours
A PA who chooses to change specialties after reaching the 4,000-hour threshold must complete the first 2,000 hours in the new specialty under the supervision of a participating physician, as described in the collaboration agreement. Collaboration in the new specialty does not begin until that 2,000-hour supervised period is complete.
The 10-Year Specialty Exception
A PA with at least 10 years or 20,000 hours of postgraduate clinical experience in a specialty may continue to provide those specialty services even if the PA is employed in a practice setting where those services fall outside the specialty of the participating physician. This exception applies only when the practice is located in a rural area or in a medically underserved area as designated by the Health Resources and Services Administration. The PA must complete continuing education related to that specialty while performing services outside the participating physician’s scope.
Physician Eligibility and the Scope of Practice Standard
A Washington participating physician must hold a current, active, and unrestricted license to practice medicine in the state. Under RCW 18.71A.010, a participating physician is defined as a physician licensed under chapter 18.71 RCW who participates in a collaboration agreement with a PA.
Washington does not impose a formal specialty alignment requirement for all PA collaboration arrangements. However, the scope of practice standard in the collaboration agreement is binding. The acts, tasks, and functions included in the agreement must be within the scope of expertise and clinical practice of the participating physician or the group of physicians in the department or specialty areas in which the PA practices. A physician who signs an agreement covering clinical areas outside their own expertise is agreeing to oversee a scope they may not be qualified to supervise.
Physician Liability
HB 2041 reduced physician liability for actions taken by PAs under collaboration agreements. The reduction in liability reflects the shift from a strict supervision model to a team-based collaboration model for experienced PAs. Physicians should confirm the specific liability protections that apply to their arrangement with a Washington healthcare attorney.
Prescriptive Authority and Controlled Substances in Washington
ARNPs in Washington may prescribe Schedule II through V controlled substances with a valid DEA registration under RCW 18.79.050. No physician agreement is required for ARNP prescribing.
For PAs, prescriptive authority is governed by the collaboration agreement. The agreement must describe the medications the PA is authorized to prescribe, which must fall within the scope of the participating physician’s clinical practice. PAs practicing under a supervision arrangement (fewer than 4,000 hours) require closer physician involvement in prescribing decisions than those operating under a full collaboration model.
Washington ARNPs authorized to prescribe must complete 15 additional continuing education hours in pharmacotherapeutics at each biennial renewal. ARNPs authorized to prescribe opioids must also complete a one-time 4-hour requirement regarding best practices in opioid prescribing.
Common Compliance Mistakes Washington Collaborating Physicians Make
Most compliance problems in Washington PA collaboration arrangements come from documentation gaps and scope mismatches.
- Agreement not updated when the PA’s hours threshold is reached. When a PA transitions from supervision to collaboration by meeting the 4,000-hour and 2,000-specialty-hour requirements, the collaboration agreement must be updated to reflect the new oversight model. Agreements that describe supervision requirements for a PA who now qualifies for collaboration do not reflect actual practice.
- Scope of practice exceeds the physician’s clinical background. The collaboration agreement can only include acts and functions within the participating physician’s own scope of expertise. Physicians who sign agreements authorizing clinical services they do not personally practice or understand create compliance exposure for both parties.
- Specialty change not documented. When a PA changes specialties, the transition to a new supervision period must be reflected in the collaboration agreement. A physician who is not aware that the PA has moved into a new specialty area may be overseeing a scope they did not agree to cover.
- Backup physician provision missing. If only one participating physician is named in the agreement and that physician is unavailable, the PA may be unable to practice. The agreement must include a protocol for designating another physician for consultation when the primary physician cannot be reached.
- Agreement not accessible at the practice location. The collaboration agreement must be available at the PA’s primary practice location, either electronically or on paper, and produced to the Washington Medical Commission upon request. Agreements stored offsite without accessible copies at the practice location create a compliance gap.
Washington Collaborating Physician Requirements: Quick Reference
NP Practice Authority
- Washington is a full practice authority state for ARNPs
- No physician collaboration agreement is required for ARNP practice or prescribing
- ARNPs may prescribe Schedule II through V controlled substances with a DEA registration
PA Collaboration Agreement Requirements
- Written collaboration agreement required before PA commences practice under RCW 18.71A.120
- Must identify at least one participating physician; signed by the participating physician or employer
- Must include: duties and responsibilities, scope of practice, communication and availability process, backup physician protocol, hours attestation, termination provision
- Available at the practice location on request; not submitted to the state
Hours Threshold (PA)
- Fewer than 4,000 hours: supervision by a participating physician required
- 4,000 or more hours plus 2,000 specialty hours: collaboration model applies
- Specialty change after 4,000 hours: 2,000 supervised hours in the new specialty required before collaboration
Physician Eligibility
- Active, unrestricted Washington MD or DO license
- Scope of practice in the agreement must fall within the physician’s own clinical expertise
Geographic Requirement
- None; physical presence at the practice site is not required for supervision but the physician must be accessible
Ratio Limit
- No statutory cap on the number of PAs a physician may collaborate with
Final Thoughts
Washington collaborating physician requirements reflect a state that has moved further than most toward provider autonomy. Full practice authority for ARNPs means the traditional NP oversight model does not apply here. The compliance framework that remains is built around PA collaboration agreements, and that framework is substantive, tiered by experience, and enforced by the Washington Medical Commission.
For physicians entering the Washington market, the key is understanding which tier of oversight applies to the PA, drafting the agreement to match that tier accurately, and keeping the document current as the PA’s practice evolves. An agreement that was correct when signed can become noncompliant when circumstances change, and the responsibility for maintaining an accurate document falls on both parties.
Build a Compliant Washington Collaboration With Collaborating Physician
If you are a licensed Washington physician interested in a structured, compliant collaboration arrangement with a PA-operated clinic, Collaborating Physician handles the infrastructure so you do not have to build it from scratch.
The platform connects licensed physicians with vetted clinics across Washington and 50-plus other states. Every agreement is structured to meet state-specific requirements, including Washington’s PA collaboration framework under RCW 18.71A and the hours-based oversight tier that applies to each arrangement. Physicians receive compliance support throughout the collaboration, not just at the start.
Applications take under ten minutes. Clinic matches typically happen within 24 to 48 hours. There is no cost to physicians at any stage.
For clinics looking for a collaborating physician, get matched fast.
Disclaimer: This content is for educational and informational purposes only. It does not constitute legal or medical advice. Washington healthcare regulations change frequently. Always verify current requirements directly with the Washington Medical Commission, the Washington State Board of Nursing, and a qualified healthcare attorney before making any practice decisions.
Frequently Asked Questions
Does Washington require a collaborating physician for nurse practitioners?
No. Washington is a full practice authority state for ARNPs. Nurse practitioners in Washington may diagnose, treat, and prescribe medications, including controlled substances, without any physician agreement under WAC 246-840-300 and RCW 18.79.250. No board filing, collaborative agreement, or transition period is required. The collaboration framework described in this guide applies to physician assistants.
When does a Washington PA move from supervision to collaboration?
A PA who has completed 4,000 or more hours of postgraduate clinical practice and 2,000 or more supervised hours in their chosen specialty may work under a collaboration model rather than a supervision model. Below that threshold, the PA must work under physician supervision. The distinction must be reflected accurately in the written collaboration agreement.
Does a Washington collaboration agreement need to be filed with the state?
No. Unlike Georgia or Pennsylvania, Washington does not require the collaboration agreement to be filed with a state agency. The agreement must be available at the PA’s primary practice location, either electronically or on paper, and produced to the Washington Medical Commission upon request. The physician should maintain their own copy.
Can a Washington PA change specialties and keep the same collaboration agreement?
Not without updating it. A PA who changes specialties after reaching 4,000 hours of experience must complete 2,000 supervised hours in the new specialty before operating under a full collaboration model in that area. The collaboration agreement must be updated to reflect the supervision requirements that apply during the specialty transition period.
Can a Washington physician be required to sign a collaboration agreement as a condition of employment?
No. Under RCW 18.71A.120(1)(c), a physician may not be compelled to participate in a collaboration agreement as a condition of employment. Participation is voluntary for both the physician and the PA.
What is the physician’s liability exposure under a Washington PA collaboration agreement?
HB 2041 reduced physician liability for actions taken by PAs under collaboration agreements, reflecting the shift toward a team-based care model. The specific liability protections that apply to a given arrangement depend on the terms of the agreement and the facts of the clinical situation. Physicians should review their liability exposure with a Washington healthcare attorney before entering into any collaboration arrangement.
