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Internal Medicine

Matthew O. Horowitz, MD

Works at hospitals in Manhasset, NY · New York

Summary

Matthew O. Horowitz, MD (Internal Medicine) is listed by Medicare at 1 hospital in Manhasset, NY. NPI 1225110901. 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 Matthew O. 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

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
YesOffers telehealth
34Years since medical school (graduated 1992)
State University Of New York At Stony Brook, School Of MedicineMedical school
MaleGender (as listed)
North Shore-Lij Medical PCGroup practice

Quick answers

Which hospitals does Matthew O. Horowitz work at?
Medicare's official clinician data lists Matthew O. Horowitz at 1 hospital: North Shore University Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Matthew O. Horowitz see patients?
Medicare's clinician data lists 7 practice locations, including Manhasset, NY and Great Neck, NY. Call before your visit to confirm the address.
What is Matthew O. Horowitz's specialty?
Medicare lists Internal Medicine as the primary specialty, and also Gastroenterology.
Does Matthew O. Horowitz accept Medicare assignment?
Yes. Medicare's clinician data says Matthew O. 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.
Does Matthew O. Horowitz offer telehealth?
Medicare's clinician data says Matthew O. Horowitz offers telehealth services. Ask the office which visits can be done by video or phone.
What is the phone number for Matthew O. Horowitz?
(516) 562-2229, as listed in official Medicare / NPI Registry data.
What is Matthew O. Horowitz's NPI number?
1225110901. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Matthew O. Horowitz works

Medicare's Facility Affiliation Data lists Matthew O. 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 Matthew O. Horowitz is enrolled with Medicare (CMS data updated 2026-10-02). The first 5 of 7; the Medicare profile lists all.

Group practices

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

  • North Shore-Lij Medical PC6,440 clinicians in the group

Specialties

Find other Internal Medicine doctors in New York →

Other internal medicine doctors in Manhasset

Clinicians with the same Medicare primary specialty in Manhasset, NY — not a recommendation.

All internal medicine doctors in Manhasset →

Clinician information

CredentialMD
Medical schoolState University Of New York At Stony Brook, School Of Medicine
Graduation year1992
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1225110901
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