Quick answers
- Does Stephanie D. Gillis accept Medicare assignment?
- Yes. Medicare's clinician data says Stephanie D. Gillis 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 Stephanie D. Gillis see?
- In 2024, CMS data shows 79 Original Medicare patients and 101 services for Stephanie D. Gillis. This counts Original Medicare only and measures volume, not quality.
- What is Stephanie D. Gillis's NPI number?
- 1871988436. 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 Stephanie D. Gillis, 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 | 79 |
|---|---|
| Services billed to Medicare | 101 |
| Different services or procedures | 40 |
| Participating Medicare provider | Yes |
| Average age of these patients | 75 |
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 cholesterol75%
- High blood pressure63%
- Arthritis58%
- Anxiety38%
- Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)33%
- Ischemic heart disease32%
Hospitals where Stephanie D. Gillis works
Medicare's Facility Affiliation Data lists Stephanie D. Gillis at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Marinhealth Medical CenterGreenbrae, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050360
Practice locations
Addresses where Stephanie D. Gillis is enrolled with Medicare (CMS data updated October 2, 2026).
- 250 Bon Air RdGreenbrae, CA 94904 (415) 925‑7000
- 347 Andrieux StSonoma, CA 95476 (707) 935‑5000
Group practices
Medicare enrollment lists Stephanie D. Gillis as a member of this group (CMS data updated October 2, 2026).
- Anesthesiology Consultants of Marin32 clinicians in the group
Specialties
- Anesthesiologyprimary
Other anesthesiologists in Greenbrae
Clinicians with the same Medicare primary specialty in Greenbrae, CA — not a recommendation.
Other clinicians in Anesthesiology Consultants of Marin
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of California, Irvine, California College Of Medicine |
| Graduation year | 2015 (11 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1871988436 |
| 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
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- 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