Quick answers
- Which hospitals does Gregory N. Geissinger work at?
- Medicare's official clinician data lists Gregory N. Geissinger at 5 hospitals: Aspirus Ironwood Hospital, Aspirus Rhinelander Hospital, Aspirus Stevens Point Hospital & Clinics, Inc., Aspirus Wausau Hospital and Marshfield Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Gregory N. Geissinger see patients?
- Medicare's clinician data lists 2 practice locations, including Marshfield, WI and Wausau, WI. Call before your visit to confirm the address.
- What is Gregory N. Geissinger's specialty?
- Medicare lists Physician Assistant as the primary specialty.
- Does Gregory N. Geissinger accept Medicare assignment?
- Yes. Medicare's clinician data says Gregory N. Geissinger 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 Gregory N. Geissinger?
- (715) 387-5511, as listed in official Medicare / NPI Registry data.
- What is Gregory N. Geissinger's NPI number?
- 1699882969. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Gregory N. Geissinger works
Medicare's Facility Affiliation Data lists Gregory N. Geissinger at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Aspirus Ironwood HospitalIronwood, MI · Critical Access Hospital · CCN 231333
- Aspirus Rhinelander HospitalRhinelander, WI · Acute Care Hospital · CCN 520019
- Aspirus Stevens Point Hospital & Clinics, Inc.Stevens Point, WI · Acute Care Hospital · CCN 520002
- Aspirus Wausau HospitalWausau, WI · Acute Care Hospital · CCN 520030
- Marshfield Medical CenterMarshfield, WI · Acute Care Hospital · CCN 520037
Practice locations
Addresses where Gregory N. Geissinger is enrolled with Medicare (CMS data updated 2026-10-02).
- 1000 N Oak AveMarshfield, WI 54449 (715) 387‑5511
- 425 Pine Ridge Blvd, Suite 300Wausau, WI 54401 (715) 847‑2070
Group practices
Medicare enrollment lists Gregory N. Geissinger as a member of these groups (CMS data updated 2026-10-02).
- MCHS Hospitals Inc1,197 clinicians in the group
- Aspirus Medical Group, Inc.268 clinicians in the group
Specialties
- Physician Assistantprimary
Other physician assistants in Marshfield
Clinicians with the same Medicare primary specialty in Marshfield, WI — not a recommendation.
Clinician information
| Credential | PA |
|---|---|
| Graduation year | 2000 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1699882969 |
| 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