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

Individual provider Internal Medicine Physician · NPI 1669819892

William C Hillmann, MD is a Hospitalist in Boston, Massachusetts. Graduated from Tufts University School of Medicine in 2013, 13 years ago. Practices with Massachusetts General Physicians Organization Inc, a 3,484-clinician group and accepts Medicare assignment. Licensed in Massachusetts.

Years since qualifying
13
Trained at
Tufts University School of Medicine
Licensed in
MA
In the registry since
2013
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Partly verified

Some contact details are missing from the federal record.

Massachusetts General Hospital 55 Fruit St
Boston, MA 02114
Phone: (617) 726-2865
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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 L-255382 (MA)

Record details

NPI number1669819892
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedMay 29, 2013
Last updated in NPPESMay 29, 2013

Medicare enrollment

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

Medicare specialtyHOSPITALIST
Also practisesINTERNAL MEDICINE
Medical schoolTUFTS UNIVERSITY SCHOOL OF MEDICINE
Graduated 2013 (13 years in practice)
Group practice Massachusetts General Physicians Organization Inc — 3484 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

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