Quick answers
- Which hospitals does Roy C. Grekin work at?
- Medicare's official clinician data lists Roy C. Grekin at 1 hospital: UCSF Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Roy C. Grekin see patients?
- Medicare's clinician data lists 2 practice locations, including San Francisco, CA. Call before your visit to confirm the address.
- What is Roy C. Grekin's specialty?
- Medicare lists Dermatology as the primary specialty.
- Does Roy C. Grekin accept Medicare assignment?
- Yes. Medicare's clinician data says Roy C. Grekin 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 Roy C. Grekin?
- (415) 476-1000, as listed in official Medicare / NPI Registry data.
- What is Roy C. Grekin's NPI number?
- 1245278506. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Roy C. Grekin works
Medicare's Facility Affiliation Data lists Roy C. Grekin at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- UCSF Medical CenterSan Francisco, CA · Acute Care Hospital · CCN 050454
Practice locations
Addresses where Roy C. Grekin is enrolled with Medicare (CMS data updated 2026-10-02).
- 1701 Divisadero StSan Francisco, CA 94115 (415) 476‑1000
- 2330 Post StSan Francisco, CA 94115 (415) 476‑4029
Group practices
Medicare enrollment lists Roy C. Grekin as a member of this group (CMS data updated 2026-10-02).
- University of California San Francisco1,839 clinicians in the group
Specialties
- Dermatologyprimary
Other dermatologists in San Francisco
Clinicians with the same Medicare primary specialty in San Francisco, CA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Michigan Medical School |
| Graduation year | 1977 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1245278506 |
| 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