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General Surgery

Hanlon B. Jen, MD

Sees patients in Fremont, CA · California

Summary

Hanlon B. Jen, MD (General Surgery) is enrolled with Medicare at 1 practice location in Fremont, CA. NPI 1891870556. Medicare data says the clinician accepts Medicare assignment. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Hanlon B. Jen, 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

General SurgeryPrimary specialty
YesAccepts Medicare assignment
30Years since medical school (graduated 1996)
MaleGender (as listed)
Permanente Medical Group IncGroup practice

Quick answers

Where does Hanlon B. Jen see patients?
Medicare's clinician data lists 1 practice location in Fremont, CA. Call before your visit to confirm the address.
What is Hanlon B. Jen's specialty?
Medicare lists General Surgery as the primary specialty.
Does Hanlon B. Jen accept Medicare assignment?
Yes. Medicare's clinician data says Hanlon B. Jen 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 Hanlon B. Jen?
(510) 248-3000, as listed in official Medicare / NPI Registry data.
What is Hanlon B. Jen's NPI number?
1891870556. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Hanlon B. Jen is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Hanlon B. Jen as a member of this group (CMS data updated 2026-10-02).

  • Permanente Medical Group Inc10,996 clinicians in the group

Specialties

Find other General Surgery doctors in California →

Other general surgeons in Fremont

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

All general surgeons in Fremont →

Clinician information

CredentialMD
Graduation year1996
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1891870556
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 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians