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

William Gionfriddo, MD

Individual provider Internal Medicine Physician · NPI 1497167936

William Gionfriddo, MD practises Internal Medicine in Boston, Massachusetts. Graduated from University of Connecticut School of Medicine in 2014, 12 years ago. Practices with Trinity Health of New England Provider Network Organization Inc, a 635-clinician group and accepts Medicare assignment. Licensed in Massachusetts.

Years since qualifying
12
Trained at
University of Connecticut School of Medicine
Licensed in
MA
In the registry since
2014
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

800 Washington St
Boston, MA 02111-1552 Not confirmed with CMS for 12 years — call before visiting
Phone: (617) 636-5000
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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 260716 (MA)

Record details

NPI number1497167936
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorYes
NPI enumeratedJune 2, 2014
Last updated in NPPESJune 2, 2014

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Medical schoolUNIVERSITY OF CONNECTICUT SCHOOL OF MEDICINE
Graduated 2014 (12 years in practice)
Group practice Trinity Health Of New England Provider Network Organization Inc — 635 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Pacemaker insertion or repair 13 times · 64th percentile

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

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 patients232
Services billed 486 a service is one billed item, such as a visit, a test or a procedure
Average patient age77

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.

Travel and Lodging $2,048 10 payments · travel or lodging paid or reimbursed, such as to attend a conference
Food and Beverage $1,176 22 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.

Colleagues at Trinity Health of New England Provider Network Organization Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 635 clinicians in the practice; 12 are shown here.

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