Quick answers
- Does John A. Zambrano accept Medicare assignment?
- Yes. Medicare's clinician data says John A. Zambrano 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 John A. Zambrano see?
- In 2024, CMS data shows 148 Original Medicare patients and 627 services for John A. Zambrano. This counts Original Medicare only and measures volume, not quality.
- What is John A. Zambrano's NPI number?
- 1730422593. 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 John A. Zambrano, 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 | 148 |
|---|---|
| Services billed to Medicare | 627 |
| Different services or procedures | 70 |
| Participating Medicare provider | Yes |
| Average age of these patients | 74 |
Most frequent services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)132 services
- Insertion of needle into vein for collection of blood sample (36415)73 services
- Blood test, lipids (cholesterol and triglycerides) (80061)39 services
- Hemoglobin a1c level (83036)37 services
- Blood creatinine level (82565)29 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 cholesterol63%
- High blood pressure56%
- Arthritis34%
- Chronic kidney disease22%
- Osteoporosis22%
- Atrial fibrillation22%
Practice locations
Addresses where John A. Zambrano is enrolled with Medicare (CMS data updated October 2, 2026).
- 147 Milk StBoston, MA 02109 (617) 654‑4700
Group practices
Medicare enrollment lists John A. Zambrano as a member of this group (CMS data updated October 2, 2026).
- Atrius Health Inc1,222 clinicians in the group
Specialties
- Internal Medicineprimary
Other internal medicine doctors in Boston
Clinicians with the same Medicare primary specialty in Boston, MA — not a recommendation.
Other clinicians in Atrius Health Inc
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 2013 (13 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1730422593 |
| 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
- 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