Quick answers
- Which hospitals does John S. Hammes work at?
- Medicare's official clinician data lists John S. Hammes at 3 hospitals: Grossmont Hospital, Scripps Mercy Hospital and Sharp Coronado Hospital and HLTHCR Ctr. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does John S. Hammes see patients?
- Medicare's clinician data lists 3 practice locations, including Coronado, CA and San Diego, CA. Call before your visit to confirm the address.
- What is John S. Hammes's specialty?
- Medicare lists Nephrology as the primary specialty, and also Internal Medicine.
- Does John S. Hammes accept Medicare assignment?
- Yes. Medicare's clinician data says John S. Hammes 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 John S. Hammes offer telehealth?
- Medicare's clinician data says John S. Hammes offers telehealth services. Ask the office which visits can be done by video or phone.
- What is the phone number for John S. Hammes?
- (619) 522-3600, as listed in official Medicare / NPI Registry data.
- What is John S. Hammes's NPI number?
- 1891766994. 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 S. Hammes works
Medicare's Facility Affiliation Data lists John S. Hammes at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Grossmont HospitalLa Mesa, CA · Acute Care Hospital · CCN 050026
- Scripps Mercy HospitalSan Diego, CA · Acute Care Hospital · CCN 050077
- Sharp Coronado Hospital and HLTHCR CtrCoronado, CA · Acute Care Hospital · CCN 050234
Practice locations
Addresses where John S. Hammes is enrolled with Medicare (CMS data updated 2026-10-02).
- 250 Prospect PlCoronado, CA 92118 (619) 522‑3600
- 7901 Frost StSan Diego, CA 92123 (858) 939‑3400
- 8885 Rio San Diego Dr, Suite 212San Diego, CA 92108 (619) 299‑2350
Group practices
Medicare enrollment lists John S. Hammes as a member of these groups (CMS data updated 2026-10-02).
- Emergency and Acute Care Medical Corporation422 clinicians in the group
- Balboa Nephrology Medical Group Inc76 clinicians in the group
Specialties
- Nephrologyprimary
- Internal Medicinealso
Other nephrologists in California
Clinicians with the same Medicare primary specialty in California — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Uniformed Services Uhs Fe Hebert School Of Med |
| Graduation year | 1993 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1891766994 |
| 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