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

David Matthew Stein, MD

Individual provider Internal Medicine Physician · NPI 1245729656

David Matthew Stein, MD practises Internal Medicine in Westborough, Massachusetts. Graduated from University of Massachusetts Medical School in 2018, 8 years ago. Practices with Reliant Medical Group Inc, a 638-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Massachusetts.

Years since qualifying
8
Trained at
University of Massachusetts Medical School
Licensed in
MA
In the registry since
2018
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

900 Union St
Westborough, MA 01581-5408
Phone: (508) 871-0700
Fax: (508) 616-4411
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence 285771 (MA)

Record details

NPI number1245729656
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedMay 2, 2018
Last updated in NPPESAugust 10, 2023
Certification dateAugust 10, 2023

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Medical schoolUNIVERSITY OF MASSACHUSETTS MEDICAL SCHOOL
Graduated 2018 (8 years in practice)
Group practice Reliant Medical Group Inc — 638 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 patients198
Services billed 781 a service is one billed item, such as a visit, a test or a procedure
Average patient age72

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 $143 7 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.

Colleagues at Reliant Medical Group Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 638 clinicians in the practice; 12 are shown here.

Other providers in Westborough