Quick answers
- Which hospitals does John E. Winterholler work at?
- Medicare's official clinician data lists John E. Winterholler at 4 hospitals: Fort Memorial Hospital, Mercy Health System Corp, UnityPoint Health - Meriter and University of WI Hospitals & Clinics Authority. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does John E. Winterholler see patients?
- Medicare's clinician data lists 6 practice locations, including Janesville, WI, Madison, WI and Richland Center, WI. Call before your visit to confirm the address.
- What is John E. Winterholler's specialty?
- Medicare lists Diagnostic Radiology as the primary specialty.
- Does John E. Winterholler accept Medicare assignment?
- Yes. Medicare's clinician data says John E. Winterholler 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 E. Winterholler?
- (608) 756-6000, as listed in official Medicare / NPI Registry data.
- What is John E. Winterholler's NPI number?
- 1912536640. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where John E. Winterholler works
Medicare's Facility Affiliation Data lists John E. Winterholler at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Fort Memorial HospitalFort Atkinson, WI · Acute Care Hospital · CCN 520071
- Mercy Health System CorpJanesville, WI · Acute Care Hospital · CCN 520066
- UnityPoint Health - MeriterMadison, WI · Acute Care Hospital · CCN 520089
- University of WI Hospitals & Clinics AuthorityMadison, WI · Acute Care Hospital · CCN 520098
Practice locations
Addresses where John E. Winterholler is enrolled with Medicare (CMS data updated 2026-10-02). The first 5 of 6; the Medicare profile lists all.
- 1000 Mineral Point AveJanesville, WI 53548 (608) 756‑6000
- 1111 Highland AveMadison, WI 53705 (608) 265‑8731
- 333 E 2nd StRichland Center, WI 53581 (608) 647‑6321
- 600 Highland AveMadison, WI 53792 (608) 263‑6400
- 611 Sherman Ave EFort Atkinson, WI 53538 (920) 568‑1000
Group practices
Medicare enrollment lists John E. Winterholler as a member of these groups (CMS data updated 2026-10-02).
- University of Wisconsin Medical Foundation Inc2,553 clinicians in the group
- Mercy Health System Corporation753 clinicians in the group
- Fort Healthcare Inc155 clinicians in the group
- University of Wisconsin System Non Payroll109 clinicians in the group
- Richland Hospital69 clinicians in the group
Specialties
- Diagnostic Radiologyprimary
Other radiologists in Janesville
Clinicians with the same Medicare primary specialty in Janesville, WI — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 2020 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1912536640 |
| Corrections | Report 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
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians