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Internal Medicine

Alexander S. Harding, MD

Works at hospitals in Boston, MA · Massachusetts

Summary

Alexander S. Harding, MD (Internal Medicine) is listed by Medicare at 1 hospital in Boston, MA. NPI 1881964153. 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 Alexander S. Harding, 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

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
11Years since medical school (graduated 2015)
Johns Hopkins University School Of MedicineMedical school
MaleGender (as listed)
The General Hospital CorporationGroup practice

Quick answers

Which hospitals does Alexander S. Harding work at?
Medicare's official clinician data lists Alexander S. Harding at 1 hospital: Massachusetts General Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Alexander S. Harding see patients?
Medicare's clinician data lists 2 practice locations, including Chelsea, MA and Boston, MA. Call before your visit to confirm the address.
What is Alexander S. Harding's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Alexander S. Harding accept Medicare assignment?
Yes. Medicare's clinician data says Alexander S. Harding 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 Alexander S. Harding?
(617) 887-4600, as listed in official Medicare / NPI Registry data.
What is Alexander S. Harding's NPI number?
1881964153. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Alexander S. Harding works

Medicare's Facility Affiliation Data lists Alexander S. Harding 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 Alexander S. Harding is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Alexander S. Harding as a member of this group (CMS data updated 2026-10-02).

  • The General Hospital Corporation1,267 clinicians in the group

Specialties

Find other Internal Medicine doctors in Massachusetts →

Other internal medicine doctors in Chelsea

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

All internal medicine doctors in Chelsea →

Clinician information

CredentialMD
Medical schoolJohns Hopkins University School Of Medicine
Graduation year2015
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1881964153
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