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

John Chiosi, MD

Individual provider Infectious Disease Physician · NPI 1306231097

John Chiosi, MD is registered under Infectious Disease in Boston, Massachusetts. Graduated from Icahn School of Medicine at Mount Sinai in 2015, 11 years ago. Practices with Mass General Brigham Medical Group Western Massachusetts Inc, a 293-clinician group, works from 2 locations, accepts Medicare assignment and offers telehealth. Licensed in Massachusetts.

Years since qualifying
11
Trained at
Icahn School of Medicine at Mount Sinai
Licensed in
MA
In the registry since
2015
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

55 Fruit St Cox 5
Boston, MA 02114
Phone: (617) 726-3906
Fax: (617) 726-7653
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 75 Francis St, Boston, MA 02115-6110 — (617) 732-5500

Specialties & licences

Infectious Disease Physician (primary) Taxonomy 207RI0200X · Licence 279009 (MA)

Record details

NPI number1306231097
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedMarch 31, 2015
Last updated in NPPESOctober 11, 2026
Certification dateOctober 11, 2026

Medicare enrollment

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

Medicare specialtyINFECTIOUS DISEASE
Medical schoolICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
Graduated 2015 (11 years in practice)
Group practice Mass General Brigham Medical Group Western Massachusetts Inc — 293 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 patients56
Services billed 151 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.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician. Those with a page here are linked.

Colleagues at Mass General Brigham Medical Group Western Massachusetts Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 293 clinicians in the practice; 12 are shown here.

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