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Dermatology

John S. Kasteler, MD

Sees patients in Gilbert, AZ · Arizona

Summary

Dr. John S. Kasteler, MD is a dermatologist at 875 N Greenfield Rd, Suite 108, Gilbert, AZ 85234. Phone: (480) 801-2103. Accepts Medicare assignment. In 2024, John S. Kasteler had 334 Original Medicare patients and 1,408 services. NPI 1487659454. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Dermatologist (Medicare lists Dermatology)
  • Address: 875 N Greenfield Rd, Suite 108, Gilbert, AZ 85234 · Directions
  • Phone: (480) 801‑2103
  • Medicare: Accepts Medicare assignment
  • Group practice: Forefront Dermatology SC
  • Medical school: University Of Utah School Of Medicine · graduated 1991 (35 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about John S. Kasteler, 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 John S. Kasteler accept Medicare assignment?
Yes. Medicare's clinician data says John S. Kasteler 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 John S. Kasteler see?
In 2024, CMS data shows 334 Original Medicare patients and 1,408 services for John S. Kasteler. This counts Original Medicare only and measures volume, not quality.
What is John S. Kasteler's NPI number?
1487659454. 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 John S. Kasteler, 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 patients334
Services billed to Medicare1,408
Different services or procedures48
Participating Medicare providerYes
Average age of these patients74

Most frequent services

  1. Destruction of precancer skin growth, 2-14 growths (17003)276 services
  2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)230 services
  3. Destruction of precancer skin growth, 1 growth (17000)217 services
  4. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)156 services
  5. Biopsy of related skin growth, first growth (11102)105 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 cholesterol72%
  • High blood pressure64%
  • Arthritis41%
  • Ischemic heart disease25%
  • Diabetes19%
  • Anxiety16%

Practice locations

Addresses where John S. Kasteler is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists John S. Kasteler as a member of this group (CMS data updated October 2, 2026).

  • Forefront Dermatology SC662 clinicians in the group

Specialties

Find other Dermatology doctors in Arizona →

Other dermatologists in Gilbert

Clinicians with the same Medicare primary specialty in Gilbert, AZ — not a recommendation.

All dermatologists in Gilbert →

Other clinicians in Forefront Dermatology SC

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

Clinician information

CredentialMD
Medical schoolUniversity Of Utah School Of Medicine
Graduation year1991 (35 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1487659454
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. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians