Quick answers
- Does Elizabeth J. Castillo accept Medicare assignment?
- Yes. Medicare's clinician data says Elizabeth J. Castillo 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 Elizabeth J. Castillo see?
- In 2024, CMS data shows 135 Original Medicare patients and 961 services for Elizabeth J. Castillo. This counts Original Medicare only and measures volume, not quality.
- What is Elizabeth J. Castillo's NPI number?
- 1932176443. 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 Elizabeth J. Castillo, 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 | 135 |
|---|---|
| Services billed to Medicare | 961 |
| Different services or procedures | 8 |
| Participating Medicare provider | Yes |
| Average age of these patients | 82 |
Most frequent services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)345 services
- Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)323 services
- Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more (99215)223 services
- Prolonged office or other outpatient evaluation and management service(s) beyond the maximum required time of the primary procedure which has been selected using total time on the date of the primary service; each additional 15 minutes by the physician or (G2212)38 services
- Advance care planning, first 30 minutes (99497)22 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 blood pressure75%
- High cholesterol75%
- Alzheimer's disease or dementia62%
- Depression53%
- Arthritis50%
- Anxiety50%
Hospitals where Elizabeth J. Castillo works
Medicare's Facility Affiliation Data lists Elizabeth J. Castillo 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.
- Beth Israel Deaconess Medical CenterBoston, MA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 220086
- Brigham and Women's HospitalBoston, MA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 220110
- Cape Cod HospitalHyannis, MA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 220012
- Falmouth HospitalFalmouth, MA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 220135
Practice locations
Addresses where Elizabeth J. Castillo is enrolled with Medicare (CMS data updated October 2, 2026).
- 55 Fruit StBoston, MA 02114 (617) 724‑0287
Group practices
Medicare enrollment lists Elizabeth J. Castillo as a member of this group (CMS data updated October 2, 2026).
- Massachusetts General Physicians Organization Inc3,558 clinicians in the group
Specialties
- Geriatric Medicineprimary
- Internal Medicinealso
Other geriatricians in Boston
Clinicians with the same Medicare primary specialty in Boston, MA — not a recommendation.
Other clinicians in Massachusetts General Physicians Organization Inc
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of California, San Francisco School Of Medicine |
| Graduation year | 2002 (24 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1932176443 |
| 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