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Ophthalmology

William S. Lim, MD

Sees patients in Riverside, CA · California

Summary

William S. Lim, MD (Ophthalmology) is enrolled with Medicare at 1 practice location in Riverside, CA. NPI 1023107380. 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 William S. Lim, 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
27Years since medical school (graduated 1999)
MaleGender (as listed)
Southern California Permanente Medical GroupGroup practice

Quick answers

Where does William S. Lim see patients?
Medicare's clinician data lists 1 practice location in Riverside, CA. Call before your visit to confirm the address.
What is William S. Lim's specialty?
Medicare lists Ophthalmology as the primary specialty.
Does William S. Lim accept Medicare assignment?
Yes. Medicare's clinician data says William S. Lim 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 William S. Lim?
(951) 353-2000, as listed in official Medicare / NPI Registry data.
What is William S. Lim's NPI number?
1023107380. 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 William S. Lim is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists William S. Lim as a member of this group (CMS data updated 2026-10-02).

  • Southern California Permanente Medical Group11,293 clinicians in the group

Specialties

Find other Ophthalmology doctors in California →

Other ophthalmologists in Riverside

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

All ophthalmologists in Riverside →

Clinician information

CredentialMD
Graduation year1999
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1023107380
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