Quick answers
- Which hospitals does John P. Oconnor work at?
- Medicare's official clinician data lists John P. Oconnor at 1 hospital: Suny/Stony Brook University Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does John P. Oconnor see patients?
- Medicare's clinician data lists 2 practice locations, including Calverton, NY. Call before your visit to confirm the address.
- What is John P. Oconnor's specialty?
- Medicare lists Internal Medicine as the primary specialty.
- Does John P. Oconnor accept Medicare assignment?
- Yes. Medicare's clinician data says John P. Oconnor 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 John P. Oconnor?
- (631) 208-2919, as listed in official Medicare / NPI Registry data.
- What is John P. Oconnor's NPI number?
- 1811917578. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where John P. Oconnor works
Medicare's Facility Affiliation Data lists John P. Oconnor at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Suny/Stony Brook University HospitalStony Brook, NY · Acute Care Hospital · CCN 330393
Practice locations
Addresses where John P. Oconnor is enrolled with Medicare (CMS data updated 2026-10-02).
- 4480 Middle Country RdCalverton, NY 11933 (631) 208‑2919
- 4480 Middle Country Rd, PO Box 667Calverton, NY 11933
Specialties
- Internal Medicineprimary
Other internal medicine doctors in New York
Clinicians with the same Medicare primary specialty in New York — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1997 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1811917578 |
| 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