Quick answers
- Which hospitals does Thomas A. Johnson work at?
- Medicare's official clinician data lists Thomas A. Johnson at 4 hospitals: Ascension Columbia St Marys Hospital Milwaukee, Ascension SE Wisconsin Hospital, Froedtert Memorial Lutheran Hospital and Waukesha Memorial Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Thomas A. Johnson see patients?
- Medicare's clinician data lists 1 practice location in Brookfield, WI. Call before your visit to confirm the address.
- What is Thomas A. Johnson's specialty?
- Medicare lists Internal Medicine as the primary specialty.
- Does Thomas A. Johnson accept Medicare assignment?
- Yes. Medicare's clinician data says Thomas A. Johnson 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 Thomas A. Johnson?
- (262) 785-1500, as listed in official Medicare / NPI Registry data.
- What is Thomas A. Johnson's NPI number?
- 1891762852. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Thomas A. Johnson works
Medicare's Facility Affiliation Data lists Thomas A. Johnson at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Ascension Columbia St Marys Hospital MilwaukeeMilwaukee, WI · Acute Care Hospital · CCN 520051
- Ascension SE Wisconsin HospitalMilwaukee, WI · Acute Care Hospital · CCN 520136
- Froedtert Memorial Lutheran HospitalMilwaukee, WI · Acute Care Hospital · CCN 520177
- Waukesha Memorial HospitalWaukesha, WI · Acute Care Hospital · CCN 520008
Practice locations
Addresses where Thomas A. Johnson is enrolled with Medicare (CMS data updated 2026-10-02).
- 17000 W N Ave, Suite 104wBrookfield, WI 53005 (262) 785‑1500
Group practices
Medicare enrollment lists Thomas A. Johnson as a member of this group (CMS data updated 2026-10-02).
- Ascension Medical Group-Southeast Wisconsin Inc545 clinicians in the group
Specialties
- Internal Medicineprimary
Other internal medicine doctors in Brookfield
Clinicians with the same Medicare primary specialty in Brookfield, WI — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Illinois College Of Med (chi/peor/rock/chm-Urb) |
| Graduation year | 1976 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1891762852 |
| 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