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Internal Medicine

Peter Mazonson, MD

Works at hospitals in San Jose, CA · California

Summary

Peter Mazonson, MD (Internal Medicine) is listed by Medicare at 1 hospital in San Jose, CA. NPI 1811953391. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Peter Mazonson, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
44Years since medical school (graduated 1982)
Geisel School Of Medicine At DartmouthMedical school
MaleGender (as listed)
County of Santa ClaraGroup practice

Quick answers

Which hospitals does Peter Mazonson work at?
Medicare's official clinician data lists Peter Mazonson at 1 hospital: Santa Clara Valley Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Peter Mazonson see patients?
Medicare's clinician data lists 2 practice locations, including San Jose, CA. Call before your visit to confirm the address.
What is Peter Mazonson's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Peter Mazonson accept Medicare assignment?
Yes. Medicare's clinician data says Peter Mazonson accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Peter Mazonson?
(408) 885-5000, as listed in official Medicare / NPI Registry data.
What is Peter Mazonson's NPI number?
1811953391. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Peter Mazonson works

Medicare's Facility Affiliation Data lists Peter Mazonson at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Peter Mazonson is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Peter Mazonson as a member of this group (CMS data updated 2026-10-02).

  • County of Santa Clara1,022 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in San Jose

Clinicians with the same Medicare primary specialty in San Jose, CA — not a recommendation.

All internal medicine doctors in San Jose →

Clinician information

CredentialMD
Medical schoolGeisel School Of Medicine At Dartmouth
Graduation year1982
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1811953391
CorrectionsReport 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

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians