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Ophthalmology

John K. Chan, MD

Sees patients in Union City, CA · California

Summary

John K. Chan, MD (Ophthalmology) is enrolled with Medicare at 1 practice location in Union City, CA. NPI 1609928837. Medicare data says the clinician accepts Medicare assignment. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about John K. Chan, 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

OphthalmologyPrimary specialty
YesAccepts Medicare assignment
29Years since medical school (graduated 1997)
New York Medical CollegeMedical school
MaleGender (as listed)
Permanente Medical Group IncGroup practice

Quick answers

Where does John K. Chan see patients?
Medicare's clinician data lists 1 practice location in Union City, CA. Call before your visit to confirm the address.
What is John K. Chan's specialty?
Medicare lists Ophthalmology as the primary specialty.
Does John K. Chan accept Medicare assignment?
Yes. Medicare's clinician data says John K. Chan 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 K. Chan?
(510) 675-4010, as listed in official Medicare / NPI Registry data.
What is John K. Chan's NPI number?
1609928837. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where John K. Chan is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists John K. Chan as a member of this group (CMS data updated 2026-10-02).

  • Permanente Medical Group Inc10,996 clinicians in the group

Specialties

Find other Ophthalmology doctors in California →

Other ophthalmologists in Union City

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

All ophthalmologists in Union City →

Clinician information

CredentialMD
Medical schoolNew York Medical College
Graduation year1997
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1609928837
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. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians