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Ophthalmology

Sean W. Tsao, MD

Sees patients in Santa Ana, CA · Anaheim, CA · Irvine, CA · California

Summary

Dr. Sean W. Tsao, MD is an ophthalmologist at 3401 S Harbor Blvd, Santa Ana, CA 92704. Phone: (888) 988-2800. Accepts Medicare assignment. In 2024, Sean W. Tsao had 15 Original Medicare patients and 118 services. NPI 1841550217. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Ophthalmologist (Medicare lists Ophthalmology)
  • Address: 3401 S Harbor Blvd, Santa Ana, CA 92704 · Directions (4 more locations)
  • Phone: (888) 988‑2800
  • Medicare: Accepts Medicare assignment
  • Group practice: Southern California Permanente Medical Group
  • Medical school: University Of California, Irvine, California College Of Medicine · graduated 2012 (14 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Sean W. Tsao, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Sean W. Tsao accept Medicare assignment?
Yes. Medicare's clinician data says Sean W. Tsao accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Sean W. Tsao see?
In 2024, CMS data shows 15 Original Medicare patients and 118 services for Sean W. Tsao. This counts Original Medicare only and measures volume, not quality.
What is Sean W. Tsao's NPI number?
1841550217. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Sean W. Tsao, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients15
Services billed to Medicare118
Different services or procedures12
Participating Medicare providerYes
Average age of these patients63

Most frequent services

  1. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)14 services

Practice locations

Addresses where Sean W. Tsao is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Sean W. Tsao as a member of this group (CMS data updated October 2, 2026).

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

Specialties

Find other Ophthalmology doctors in California →

Other ophthalmologists in Santa Ana

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

All ophthalmologists in Santa Ana →

Other clinicians in Southern California Permanente Medical Group

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Medical schoolUniversity Of California, Irvine, California College Of Medicine
Graduation year2012 (14 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1841550217
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 October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  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