Quick answers
- Which hospitals does Howard J. Greenberg work at?
- Medicare's official clinician data lists Howard J. Greenberg at 1 hospital: Mount Sinai Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Howard J. Greenberg see patients?
- Medicare's clinician data lists 1 practice location in Greenlawn, NY. Call before your visit to confirm the address.
- What is Howard J. Greenberg's specialty?
- Medicare lists Hematology/Oncology as the primary specialty.
- Does Howard J. Greenberg accept Medicare assignment?
- Yes. Medicare's clinician data says Howard J. Greenberg 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 Howard J. Greenberg?
- (631) 628-5000, as listed in official Medicare / NPI Registry data.
- What is Howard J. Greenberg's NPI number?
- 1104847508. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Howard J. Greenberg works
Medicare's Facility Affiliation Data lists Howard J. Greenberg at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Mount Sinai HospitalNew York, NY · Acute Care Hospital · CCN 330024
Practice locations
Addresses where Howard J. Greenberg is enrolled with Medicare (CMS data updated 2026-10-02).
- 5 Cuba Hill RdGreenlawn, NY 11740 (631) 628‑5000
Group practices
Medicare enrollment lists Howard J. Greenberg as a member of this group (CMS data updated 2026-10-02).
- North Shore Medical Group of the Mount Sinai School of Medicine331 clinicians in the group
Specialties
- Hematology/Oncologyprimary
Other hematologist-oncologists in New York
Clinicians with the same Medicare primary specialty in New York — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | State University Of New York Downstate Medical Center |
| Graduation year | 1973 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1104847508 |
| Corrections | Report 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
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians