Quick answers
- Does Diana M. Mak accept Medicare assignment?
- Yes. Medicare's clinician data says Diana M. Mak 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.
- What is Diana M. Mak's NPI number?
- 1104936988. 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 Diana M. Mak is enrolled with Medicare (CMS data updated October 2, 2026).
- 9089 Baseline RdRancho Cucamonga, CA 91730 (909) 941‑9927
Group practices
Medicare enrollment lists Diana M. Mak as a member of this group (CMS data updated October 2, 2026).
- Inland Physicians Service Inc2 clinicians in the group
Specialties
- Family Practiceprimary
Other family doctors in Rancho Cucamonga
Clinicians with the same Medicare primary specialty in Rancho Cucamonga, CA — not a recommendation.
Other clinicians in Inland Physicians Service Inc
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | DO |
|---|---|
| Medical school | Michigan State University College Of Osteopathic Medicine |
| Graduation year | 1981 (45 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1104936988 |
| 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
- 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