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

Dr. Mark Thomas Day, DO

Individual provider Internal Medicine Physician · NPI 1225492796

Dr. Mark Thomas Day, DO practises Internal Medicine in Lebanon, Oregon. Graduated from Des Moines University of Osteopathic Medicine and Health Sciences in 2017, 9 years ago. Practices with Legacy Good Samaritan Hospital and Medical Center, a 192-clinician group, works from 2 locations, accepts Medicare assignment and offers telehealth. Licensed in Oregon.

Years since qualifying
9
Trained at
Des Moines University of Osteopathic Medicine and Health Sciences
Licensed in
OR
In the registry since
2016
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

525 N Santiam Hwy
Lebanon, OR 97355-4363
Phone: (541) 258-2101
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 3600 Nw Samaritan Dr, Corvallis, OR 97330-3737 — (541) 768-4906

Specialties & licences

Cardiovascular Disease Physician (primary) Taxonomy 207RC0000X · Licence DO197880 (OR)
Internal Medicine Physician Taxonomy 207R00000X · Licence 182616 (OR)
Student in an Organized Health Care Education/Training Program Taxonomy 390200000X

Record details

NPI number1225492796
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorNo
NPI enumeratedApril 11, 2016
Last updated in NPPESFebruary 28, 2023
Certification dateFebruary 28, 2023

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Medical schoolDES MOINES UNIVERSITY OF OSTEOPATHIC MEDICINE AND HEALTH SCIENCES
Graduated 2017 (9 years in practice)
Group practice Legacy Good Samaritan Hospital And Medical Center — 192 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations6 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 patients520
Services billed 1,050 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 $418 13 payments · 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. Those with a page here are linked.

  • Legacy Good Samaritan Medical Center Hospital · Portland, OR · listed as Legacy Good Samaritan Hospital and Medical Center
  • Legacy Mount Hood Medical Center Hospital · Gresham, OR
  • Legacy Emanuel Medical Center Hospital · Portland, OR
  • Legacy Meridian Park Medical Center Hospital · Tualatin, OR
  • Legacy Salmon Creek Medical Center Hospital · Vancouver, WA

Colleagues at Legacy Good Samaritan Hospital and Medical Center

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 192 clinicians in the practice; 12 are shown here.

Other providers in Lebanon