Quick answers
- Does Ellen J. Zemarkowitz accept Medicare assignment?
- Medicare's clinician data says Ellen J. Zemarkowitz may accept Medicare assignment (as of October 2, 2026). Ask the office whether they accept it for your visit.
- What is Ellen J. Zemarkowitz's NPI number?
- 1053252957. 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 Ellen J. Zemarkowitz is enrolled with Medicare (CMS data updated October 2, 2026).
- 500 Pasteur Dr, Rm P388Palo Alto, CA 94304
Specialties
- Clinical Social Workerprimary
Other clinical social workers in Palo Alto
Clinicians with the same Medicare primary specialty in Palo Alto, CA — not a recommendation.
Clinician information
| Credential | CSW |
|---|---|
| Graduation year | 2015 |
| Gender (as listed) | Female |
| Medicare assignment | May accept for some services |
| NPI (National Provider Identifier) | 1053252957 |
| 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