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Internal Medicine

Thomas L. Chen, MD

Works at hospitals in Fremont, CA · San Leandro, CA · California

Summary

Thomas L. Chen, MD (Internal Medicine) is listed by Medicare at 2 hospitals in Fremont, CA and San Leandro, CA. NPI 1699112458. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Thomas L. Chen, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
13Years since medical school (graduated 2013)
Tulane University School Of MedicineMedical school
MaleGender (as listed)
Permanente Medical Group IncGroup practice

Quick answers

Which hospitals does Thomas L. Chen work at?
Medicare's official clinician data lists Thomas L. Chen at 2 hospitals: Kaiser Foundation Hospital - Fremont and Kaiser Foundation Hospital - San Leandro. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Thomas L. Chen see patients?
Medicare's clinician data lists 1 practice location in Fremont, CA. Call before your visit to confirm the address.
What is Thomas L. Chen's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Thomas L. Chen accept Medicare assignment?
Yes. Medicare's clinician data says Thomas L. Chen 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 Thomas L. Chen?
(510) 248-3000, as listed in official Medicare / NPI Registry data.
What is Thomas L. Chen's NPI number?
1699112458. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Thomas L. Chen works

Medicare's Facility Affiliation Data lists Thomas L. Chen at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Thomas L. Chen is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Thomas L. Chen as a member of this group (CMS data updated 2026-10-02).

  • Permanente Medical Group Inc10,996 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Fremont

Clinicians with the same Medicare primary specialty in Fremont, CA — not a recommendation.

All internal medicine doctors in Fremont →

Clinician information

CredentialMD
Medical schoolTulane University School Of Medicine
Graduation year2013
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1699112458
CorrectionsReport 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

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians