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Family Practice

Jean J. Yoshioka, MD

Sees patients in Napa, CA · California

Summary

Dr. Jean J. Yoshioka, MD is a family doctor at 3285 Claremont Way, Napa, CA 94558. Phone: (707) 258-2500. Accepts Medicare assignment. In 2024, Jean J. Yoshioka had 12 Original Medicare patients and 17 services. NPI 1023135654. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Family doctor (Medicare lists Family Practice)
  • Address: 3285 Claremont Way, Napa, CA 94558 · Directions
  • Phone: (707) 258‑2500
  • Medicare: Accepts Medicare assignment
  • Group practice: Permanente Medical Group Inc
  • Medical school: Loma Linda University School Of Medicine · graduated 2004 (22 years since medical school)
  • Gender (as listed): Female
  • Telehealth: offered

From official Medicare data

This page shows what Medicare's official clinician data says about Jean J. Yoshioka, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Jean J. Yoshioka accept Medicare assignment?
Yes. Medicare's clinician data says Jean J. Yoshioka 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 Jean J. Yoshioka see?
In 2024, CMS data shows 12 Original Medicare patients and 17 services for Jean J. Yoshioka. This counts Original Medicare only and measures volume, not quality.
What is Jean J. Yoshioka's NPI number?
1023135654. 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 Jean J. Yoshioka, 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 patients12
Services billed to Medicare17
Different services or procedures5
Participating Medicare providerYes
Average age of these patients67

Practice locations

Addresses where Jean J. Yoshioka is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Jean J. Yoshioka as a member of this group (CMS data updated October 2, 2026).

  • Permanente Medical Group Inc10,996 clinicians in the group

Specialties

Find other Family Practice doctors in California →

Other family doctors in Napa

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

All family doctors in Napa →

Other clinicians in Permanente Medical Group Inc

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Medical schoolLoma Linda University School Of Medicine
Graduation year2004 (22 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1023135654
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. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  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