Quick answers
- Where does Mary Leong see patients?
- Medicare's clinician data lists 2 practice locations, including Brentwood, CA and Antioch, CA. Call before your visit to confirm the address.
- What is Mary Leong's specialty?
- Medicare lists Optometry as the primary specialty.
- Does Mary Leong accept Medicare assignment?
- Yes. Medicare's clinician data says Mary Leong 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 Mary Leong?
- (925) 513-0323, as listed in official Medicare / NPI Registry data.
- What is Mary Leong's NPI number?
- 1003968249. 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 Mary Leong is enrolled with Medicare (CMS data updated 2026-10-02).
- 3840 Balfour Rd, ABrentwood, CA 94513 (925) 513‑0323
- 5109 Lone Tree WayAntioch, CA 94531 (925) 757‑5577
Group practices
Medicare enrollment lists Mary Leong as a member of these groups (CMS data updated 2026-10-02).
- 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.
Clinician information
| Credential | OD |
|---|---|
| Medical school | Southern California College Of Optometry |
| Graduation year | 2002 |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1003968249 |
| 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 2026-10-02, retrieved 2026-10-29
- 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