Quick answers
- Which hospitals does John Y. Kim work at?
- Medicare's official clinician data lists John Y. Kim at 1 hospital: Kaiser Foundation Hospital - Walnut Creek. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does John Y. Kim see patients?
- Medicare's clinician data lists 5 practice locations, including Walnut Creek, CA, Pleasanton, CA and Richmond, CA. Call before your visit to confirm the address.
- What is John Y. Kim's specialty?
- Medicare lists Internal Medicine as the primary specialty.
- Does John Y. Kim accept Medicare assignment?
- Yes. Medicare's clinician data says John Y. Kim 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 Y. Kim?
- (925) 295-4000, as listed in official Medicare / NPI Registry data.
- What is John Y. Kim's NPI number?
- 1124107883. 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 Y. Kim works
Medicare's Facility Affiliation Data lists John Y. Kim at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Kaiser Foundation Hospital - Walnut CreekWalnut Creek, CA · Acute Care Hospital · CCN 050072
Practice locations
Addresses where John Y. Kim is enrolled with Medicare (CMS data updated 2026-10-02).
- 1425 S Main StWalnut Creek, CA 94596 (925) 295‑4000
- 5820 Owens DrPleasanton, CA 94588
- 5820 Owens Dr Bldg E 2nd FloorPleasanton, CA 94588
- 5820 Owens Dr Building E 2nd Floor, Tpmg Hr Compliance and EnrollmentPleasanton, CA 94588
- 901 Nevin AveRichmond, CA 94801 (510) 307‑1500
Group practices
Medicare enrollment lists John Y. Kim as a member of this group (CMS data updated 2026-10-02).
- Permanente Medical Group Inc10,996 clinicians in the group
Specialties
- Internal Medicineprimary
Other internal medicine doctors in Walnut Creek
Clinicians with the same Medicare primary specialty in Walnut Creek, CA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | New York Medical College |
| Graduation year | 1999 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1124107883 |
| 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