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Internal Medicine

Mack L. Sullivan, MD

Sees patients in Eastchester, NY · New York

Summary

Mack L. Sullivan, MD (Internal Medicine) is enrolled with Medicare at 1 practice location in Eastchester, NY. NPI 1881616068. Medicare data says the clinician accepts Medicare assignment. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Mack L. Sullivan, 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
31Years since medical school (graduated 1995)
Albert Einstein College Of Medicine Of Yeshiva UniversityMedical school
MaleGender (as listed)

Quick answers

Where does Mack L. Sullivan see patients?
Medicare's clinician data lists 1 practice location in Eastchester, NY. Call before your visit to confirm the address.
What is Mack L. Sullivan's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Mack L. Sullivan accept Medicare assignment?
Yes. Medicare's clinician data says Mack L. Sullivan 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 Mack L. Sullivan?
(914) 395-3691, as listed in official Medicare / NPI Registry data.
What is Mack L. Sullivan's NPI number?
1881616068. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Mack L. Sullivan is enrolled with Medicare (CMS data updated 2026-10-02).

Specialties

Find other Internal Medicine doctors in New York →

Other internal medicine doctors in Eastchester

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

All internal medicine doctors in Eastchester →

Clinician information

CredentialMD
Medical schoolAlbert Einstein College Of Medicine Of Yeshiva University
Graduation year1995
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1881616068
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. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians