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Colorectal Surgery (Proctology)

Ngoc P. Nguyen, MD

Works at hospitals in Fontana, CA · California

Summary

Dr. Ngoc P. Nguyen, MD is a colorectal surgeon at 9961 Sierra Ave, Fontana, CA 92335. Phone: (909) 427-5000. Accepts Medicare assignment. NPI 1417153552. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026.

  • Specialty: Colorectal surgeon (Medicare lists Colorectal Surgery (Proctology))
  • Address: 9961 Sierra Ave, Fontana, CA 92335 · Directions
  • Phone: (909) 427‑5000
  • Medicare: Accepts Medicare assignment
  • Hospital: Kaiser Foundation Hospital Fontana/Ontario
  • Group practice: Southern California Permanente Medical Group
  • Medical school: University Of Nebraska College Of Medicine · graduated 1989 (37 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Ngoc P. 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 Ngoc P. Nguyen accept Medicare assignment?
Yes. Medicare's clinician data says Ngoc P. 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.
What is Ngoc P. Nguyen's NPI number?
1417153552. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Ngoc P. Nguyen works

Medicare's Facility Affiliation Data lists Ngoc P. 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 Ngoc P. Nguyen is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Ngoc P. 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 Colorectal Surgery (Proctology) doctors in California →

Other colorectal surgeons in California

Clinicians with the same Medicare primary specialty in California — not a recommendation.

All colorectal surgeons in California →

Other clinicians in Southern California Permanente Medical Group

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

Clinician information

CredentialMD
Medical schoolUniversity Of Nebraska College Of Medicine
Graduation year1989 (37 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1417153552
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. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  5. Medicare Care Compare — official Medicare tool to look up clinicians