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Internal Medicine

Ambreen Hasan, MD

Sees patients in Fontana, CA · California

Summary

Ambreen Hasan, MD (Internal Medicine) is enrolled with Medicare at 1 practice location in Fontana, CA. NPI 1265600910. 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 Ambreen Hasan, 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
26Years since medical school (graduated 2000)
FemaleGender (as listed)
Southern California Permanente Medical GroupGroup practice

Quick answers

Where does Ambreen Hasan see patients?
Medicare's clinician data lists 1 practice location in Fontana, CA. Call before your visit to confirm the address.
What is Ambreen Hasan's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Ambreen Hasan accept Medicare assignment?
Yes. Medicare's clinician data says Ambreen Hasan 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 Ambreen Hasan?
(909) 427-5000, as listed in official Medicare / NPI Registry data.
What is Ambreen Hasan's NPI number?
1265600910. 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 Ambreen Hasan is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

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

  • Southern California Permanente Medical Group11,293 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Fontana

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

All internal medicine doctors in Fontana →

Clinician information

CredentialMD
Graduation year2000
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1265600910
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