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Pediatric Medicine

Karen Kay G. Alfonso, MD

Sees patients in Chino Hills, CA · Apple Valley, CA · California

Summary

Dr. Karen Kay G. Alfonso, MD is a pediatrician at 15855 Pomona Rincon Rd, Bldg 4, Chino Hills, CA 91709. Phone: (909) 929-2511. Accepts Medicare assignment. NPI 1316228729. Source: CMS National Downloadable File, updated October 2, 2026.

  • Specialty: Pediatrician (Medicare lists Pediatric Medicine)
  • Address: 15855 Pomona Rincon Rd, Bldg 4, Chino Hills, CA 91709 · Directions (1 more location)
  • Phone: (909) 929‑2511
  • Medicare: Accepts Medicare assignment
  • Group practice: Providence Medical Foundation
  • Medical school: graduated 2013 (13 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Karen Kay G. Alfonso, 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 Karen Kay G. Alfonso accept Medicare assignment?
Yes. Medicare's clinician data says Karen Kay G. Alfonso 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 Karen Kay G. Alfonso's NPI number?
1316228729. 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 Karen Kay G. Alfonso is enrolled with Medicare (CMS data updated October 2, 2026).

  • 15855 Pomona Rincon Rd, Bldg 4Chino Hills, CA 91709 (909) 929‑2511
  • 19333 Bear Valley RdApple Valley, CA 92308

Group practices

Medicare enrollment lists Karen Kay G. Alfonso as a member of this group (CMS data updated October 2, 2026).

  • Providence Medical Foundation1,466 clinicians in the group

Specialties

Find other Pediatric Medicine doctors in California →

Other pediatricians in California

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

All pediatricians in California →

Other clinicians in Providence Medical Foundation

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

Clinician information

CredentialMD
Graduation year2013 (13 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1316228729
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 October 2, 2026, retrieved October 29, 2026
  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