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Pathology

Gary L. Horowitz, MD

Works at hospitals in Lowell, MA · Melrose, MA · Framingham, MA … · Massachusetts

Summary

Gary L. Horowitz, MD (Pathology) is listed by Medicare at 4 hospitals in Lowell, MA, Melrose, MA and Framingham, MA and other places. NPI 1558308213. 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 Gary L. Horowitz, 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

PathologyPrimary specialty
YesAccepts Medicare assignment
50Years since medical school (graduated 1976)
Harvard Medical SchoolMedical school
MaleGender (as listed)
Pratt Pathology Associates IncGroup practice

Quick answers

Which hospitals does Gary L. Horowitz work at?
Medicare's official clinician data lists Gary L. Horowitz at 4 hospitals: Lowell General Hospital, Melrosewakefield Healthcare, Metrowest Medical Center and Tufts Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Gary L. Horowitz see patients?
Medicare's clinician data lists 1 practice location in Boston, MA. Call before your visit to confirm the address.
What is Gary L. Horowitz's specialty?
Medicare lists Pathology as the primary specialty.
Does Gary L. Horowitz accept Medicare assignment?
Yes. Medicare's clinician data says Gary L. Horowitz 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 Gary L. Horowitz?
(617) 636-5000, as listed in official Medicare / NPI Registry data.
What is Gary L. Horowitz's NPI number?
1558308213. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Gary L. Horowitz works

Medicare's Facility Affiliation Data lists Gary L. Horowitz 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 Gary L. Horowitz is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Gary L. Horowitz as a member of this group (CMS data updated 2026-10-02).

  • Pratt Pathology Associates Inc25 clinicians in the group

Specialties

Find other Pathology doctors in Massachusetts →

Other pathologists in Boston

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

All pathologists in Boston →

Clinician information

CredentialMD
Medical schoolHarvard Medical School
Graduation year1976
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1558308213
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