Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Robert A Mairs, DO

Individual provider Gynecology Physician · NPI 1124001862

Robert A Mairs, DO practises Obstetrics/Gynecology in Ontario, Oregon. Graduated from At Still University of Health Sciences, College of Osteo Med, Kirksville in 1993, 33 years ago. Practices with Saint Alphonsus Medical Center- Ontario Inc, a 41-clinician group, works from 3 locations and accepts Medicare assignment. Licensed in Idaho and Oregon.

Years since qualifying
33
Trained at
At Still University of Health Sciences, College of Osteo Med, Kirksville
Licensed in
ID, OR
In the registry since
2005
Specialties on file
3
What do these letters mean?
DO — Doctor of Osteopathic Medicine
A fully licensed physician, trained like an MD with additional musculoskeletal training. Equivalent practice rights in all 50 states.

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Practice location Address checks out

1050 SW 3rd Ave Ste 3200
Ontario, OR 97914-4560
Phone: (541) 881-2325
Fax: (208) 914-6701
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (2)

  • 9850 W St Lukes Dr Ste 320a, Nampa, ID 83687-7912 — (208) 706-3220
  • 840 Sw 4th Ave Ste 105, Ontario, OR 97914-2638 — (541) 881-2800

Specialties & licences

Obstetrics & Gynecology Physician (primary) Taxonomy 207V00000X · Licence DO20644 (OR)
Gynecology Physician Taxonomy 207VG0400X · Licence O-186 (ID)
Gynecology Physician Taxonomy 207VG0400X · Licence DO20644 (OR)

Record details

NPI number1124001862
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorNo
NPI enumeratedNovember 28, 2005
Last updated in NPPESSeptember 23, 2025
Certification dateSeptember 23, 2025

Medicare enrollment

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

Medicare specialtyOBSTETRICS/GYNECOLOGY
Medical schoolAT STILL UNIVERSITY OF HEALTH SCIENCES, COLLEGE OF OSTEO MED, KIRKSVILLE
Graduated 1993 (33 years in practice)
Group practice Saint Alphonsus Medical Center- Ontario Inc — 41 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations7 on file with Medicare

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 patients20
Services billed 30 a service is one billed item, such as a visit, a test or a procedure
Average patient age70

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 $17 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.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Saint Alphonsus Medical Center- Ontario Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 41 clinicians in the practice; 12 are shown here.