Quick answers
- Where does Stephen G. Sisselman see patients?
- Medicare's clinician data lists 2 practice locations, including Commack, NY and Massapequa, NY. Call before your visit to confirm the address.
- What is Stephen G. Sisselman's specialty?
- Medicare lists Internal Medicine as the primary specialty.
- Does Stephen G. Sisselman accept Medicare assignment?
- Yes. Medicare's clinician data says Stephen G. Sisselman 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 Stephen G. Sisselman offer telehealth?
- Medicare's clinician data says Stephen G. Sisselman offers telehealth services. Ask the office which visits can be done by video or phone.
- What is the phone number for Stephen G. Sisselman?
- (631) 670-6525, as listed in official Medicare / NPI Registry data.
- What is Stephen G. Sisselman's NPI number?
- 1609948884. 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 Stephen G. Sisselman is enrolled with Medicare (CMS data updated 2026-10-02).
- 2171 Jericho Tpke, Suite 135Commack, NY 11725 (631) 670‑6525
- 627 BroadwayMassapequa, NY 11758 (516) 308‑4040
Group practices
Medicare enrollment lists Stephen G. Sisselman as a member of this group (CMS data updated 2026-10-02).
- Sisselman Medical Group PC5 clinicians in the group
Specialties
- Internal Medicineprimary
Other internal medicine doctors in Commack
Clinicians with the same Medicare primary specialty in Commack, NY — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | New York College Of Osteo Medicine Of New York Institute Of Technology |
| Graduation year | 1996 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1609948884 |
| 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
- 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