Medical emergency?Emergency? Call 911. Nearest emergency roomsNearest ERs

Emergency Medicine

Tina A. Nguyen, MD

Works at hospitals in Fontana, CA · California

Summary

Dr. Tina A. Nguyen, MD is an emergency medicine doctor at 2295 S Vineyard Ave, Ontario, CA 91761. Phone: (909) 724-5000. Accepts Medicare assignment. In 2024, Tina A. Nguyen had 28 Original Medicare patients and 28 services. NPI 1174789630. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Emergency medicine doctor (Medicare lists Emergency Medicine)
  • Address: 2295 S Vineyard Ave, Ontario, CA 91761 · Directions (1 more location)
  • Phone: (909) 724‑5000
  • Medicare: Accepts Medicare assignment
  • Hospital: Kaiser Foundation Hospital Fontana/Ontario
  • Group practice: Southern California Permanente Medical Group
  • Medical school: graduated 2008 (18 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Tina A. Nguyen, 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 Tina A. Nguyen accept Medicare assignment?
Yes. Medicare's clinician data says Tina A. Nguyen 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 Tina A. Nguyen see?
In 2024, CMS data shows 28 Original Medicare patients and 28 services for Tina A. Nguyen. This counts Original Medicare only and measures volume, not quality.
What is Tina A. Nguyen's NPI number?
1174789630. 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 Tina A. Nguyen, 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 patients28
Services billed to Medicare28
Different services or procedures5
Participating Medicare providerYes
Average age of these patients63

Most frequent services

  1. Emergency department visit with moderate level of medical decision making (99284)19 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 blood pressure75%
  • High cholesterol61%
  • Diabetes54%
  • Arthritis50%

Hospitals where Tina A. Nguyen works

Medicare's Facility Affiliation Data lists Tina A. Nguyen at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

Practice locations

Addresses where Tina A. Nguyen is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Tina A. Nguyen as a member of this group (CMS data updated October 2, 2026).

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

Specialties

Find other Emergency Medicine doctors in California →

Other emergency medicine doctors in Ontario

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

All emergency medicine doctors in Ontario →

Other clinicians in Southern California Permanente Medical Group

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

Clinician information

CredentialMD
Graduation year2008 (18 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1174789630
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 October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians