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Anesthesiology

John T. Ley, MD

Sees patients in Fontana, CA · California

Summary

John T. Ley, MD (Anesthesiology) is enrolled with Medicare at 1 practice location in Fontana, CA. NPI 1811290679. 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 John T. Ley, 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

AnesthesiologyPrimary specialty
YesAccepts Medicare assignment
20Years since medical school (graduated 2006)
Toledo Medical CollegeMedical school
MaleGender (as listed)
Southern California Permanente Medical GroupGroup practice

Quick answers

Where does John T. Ley see patients?
Medicare's clinician data lists 1 practice location in Fontana, CA. Call before your visit to confirm the address.
What is John T. Ley's specialty?
Medicare lists Anesthesiology as the primary specialty.
Does John T. Ley accept Medicare assignment?
Yes. Medicare's clinician data says John T. Ley 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 John T. Ley?
(909) 427-5000, as listed in official Medicare / NPI Registry data.
What is John T. Ley's NPI number?
1811290679. 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 John T. Ley is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists John T. Ley 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 Anesthesiology doctors in California →

Other anesthesiologists in Fontana

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

All anesthesiologists in Fontana →

Clinician information

CredentialMD
Medical schoolToledo Medical College
Graduation year2006
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1811290679
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