Quick answers
- Where does Stephen M. Castaldi see patients?
- Medicare's clinician data lists 2 practice locations, including Williamsville, NY and North Tonawanda, NY. Call before your visit to confirm the address.
- What is Stephen M. Castaldi's specialty?
- Medicare lists Physician Assistant as the primary specialty.
- Does Stephen M. Castaldi accept Medicare assignment?
- Yes. Medicare's clinician data says Stephen M. Castaldi 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 Stephen M. Castaldi?
- (716) 568-3600, as listed in official Medicare / NPI Registry data.
- What is Stephen M. Castaldi's NPI number?
- 1982558680. 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 M. Castaldi is enrolled with Medicare (CMS data updated 2026-10-02).
- 1540 Maple RdWilliamsville, NY 14221 (716) 568‑3600
- 445 Tremont StNorth Tonawanda, NY 14120 (716) 694‑4500
Group practices
Medicare enrollment lists Stephen M. Castaldi as a member of this group (CMS data updated 2026-10-02).
- University Emergency Medical Services Inc.95 clinicians in the group
Specialties
- Physician Assistantprimary
Other physician assistants in Williamsville
Clinicians with the same Medicare primary specialty in Williamsville, NY — not a recommendation.
Clinician information
| Credential | PA |
|---|---|
| Graduation year | 2025 |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1982558680 |
| 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