Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Mr. Mark Lewis Anstadt, ARNP

Individual provider Nurse Practitioner · NPI 1144414145

Mr. Mark Lewis Anstadt, ARNP is a Nurse Practitioner in Seattle, Washington. Graduated from University of Washington School of Medicine in 2007, 19 years ago. Practices with The Polyclinic PLLC, a 366-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Washington.

Years since qualifying
19
Trained at
University of Washington School of Medicine
Licensed in
WA
In the registry since
2007
What do these letters mean?
ARNP — Advanced Registered Nurse Practitioner
The title some states use for an advanced practice nurse.

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Practice location Address checks out

904 7th Ave
Seattle, WA 98104
Phone: (206) 860-5603
Fax: (206) 720-7459
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Nurse Practitioner (primary) Taxonomy 363L00000X · Licence AP30007837 (WA)

Record details

NPI number1144414145
Entity typeIndividual (Type 1)
GenderMale
Credentials ARNP
Sole proprietorNo
NPI enumeratedSeptember 1, 2007
Last updated in NPPESJune 29, 2026
Certification dateJune 29, 2026

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyNURSE PRACTITIONER
Medical schoolUNIVERSITY OF WASHINGTON SCHOOL OF MEDICINE
Graduated 2007 (19 years in practice)
Group practice The Polyclinic Pllc — 366 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients125
Services billed 1,135 a service is one billed item, such as a visit, a test or a procedure
Average patient age73

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $14 1 payment · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Colleagues at The Polyclinic PLLC

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 366 clinicians in the practice; 12 are shown here.

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