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Gastroenterology

Maureen M. Leonard, MD

Works at hospitals in Boston, MA · Massachusetts

Summary

Maureen M. Leonard, MD (Gastroenterology) is listed by Medicare at 1 hospital in Boston, MA. NPI 1336374552. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Maureen M. Leonard, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

GastroenterologyPrimary specialty
YesAccepts Medicare assignment
17Years since medical school (graduated 2009)
New York University School Of MedicineMedical school
FemaleGender (as listed)
The General Hospital CorporationGroup practice

Quick answers

Which hospitals does Maureen M. Leonard work at?
Medicare's official clinician data lists Maureen M. Leonard at 1 hospital: Massachusetts General Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Maureen M. Leonard see patients?
Medicare's clinician data lists 1 practice location in Boston, MA. Call before your visit to confirm the address.
What is Maureen M. Leonard's specialty?
Medicare lists Gastroenterology as the primary specialty, and also Pediatric Medicine.
Does Maureen M. Leonard accept Medicare assignment?
Yes. Medicare's clinician data says Maureen M. Leonard accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Maureen M. Leonard?
(617) 726-2000, as listed in official Medicare / NPI Registry data.
What is Maureen M. Leonard's NPI number?
1336374552. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Maureen M. Leonard works

Medicare's Facility Affiliation Data lists Maureen M. Leonard at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Maureen M. Leonard is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Maureen M. Leonard as a member of this group (CMS data updated 2026-10-02).

  • The General Hospital Corporation1,267 clinicians in the group

Specialties

Find other Gastroenterology doctors in Massachusetts →

Other gastroenterologists in Boston

Clinicians with the same Medicare primary specialty in Boston, MA — not a recommendation.

All gastroenterologists in Boston →

Clinician information

CredentialMD
Medical schoolNew York University School Of Medicine
Graduation year2009
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1336374552
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians