Quick answers
- Does Winson T. Ong accept Medicare assignment?
- Yes. Medicare's clinician data says Winson T. Ong 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 Winson T. Ong see?
- In 2024, CMS data shows 82 Original Medicare patients and 199 services for Winson T. Ong. This counts Original Medicare only and measures volume, not quality.
- What is Winson T. Ong's NPI number?
- 1821132143. 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 Winson T. Ong, 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 patients | 82 |
|---|---|
| Services billed to Medicare | 199 |
| Different services or procedures | 16 |
| Participating Medicare provider | Yes |
| Average age of these patients | 76 |
Most frequent services
- Established patient complete exam of visual system (92014)57 services
- Photography of the retina (92250)42 services
- Established patient problem focused exam of visual system (92012)32 services
- Exam of visual field with extended testing (92083)17 services
- Imaging of optic nerve (92133)14 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High cholesterol74%
- High blood pressure67%
- Arthritis41%
- Chronic kidney disease28%
- Diabetes24%
- Atrial fibrillation16%
Practice locations
Addresses where Winson T. Ong is enrolled with Medicare (CMS data updated October 2, 2026).
- 3840 Balfour Rd, ABrentwood, CA 94513 (925) 513‑0323
- 5109 Lone Tree WayAntioch, CA 94531 (925) 757‑5577
- 6500 Dublin Blvd, Suite FDublin, CA 94568 (925) 828‑7730
Group practices
Medicare enrollment lists Winson T. Ong as a member of these groups (CMS data updated October 2, 2026).
- Balfour Vision Optix Optometry Inc3 clinicians in the group
- Winson Ong Od3 clinicians in the group
Specialties
- Optometryprimary
Other optometrists in Brentwood
Clinicians with the same Medicare primary specialty in Brentwood, CA — not a recommendation.
Other clinicians in Balfour Vision Optix Optometry Inc
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | OD |
|---|---|
| Optometry school | University Of California - School Of Optometry |
| Graduation year | 2002 (24 years since optometry school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1821132143 |
| 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
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- 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