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Family Practice

Spencer W. Fast, MD

Works at hospitals in Weston, WI · Reedsburg, WI · Madison, WI · Wisconsin

Summary

Spencer W. Fast, MD (Family Practice) is listed by Medicare at 3 hospitals in Weston, WI, Reedsburg, WI and Madison, WI. NPI 1306990429. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Spencer W. Fast, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Family PracticePrimary specialty
YesAccepts Medicare assignment
21Years since medical school (graduated 2005)
Medical College Of WisconsinMedical school
MaleGender (as listed)
MCHS Hospitals IncGroup practice

Quick answers

Which hospitals does Spencer W. Fast work at?
Medicare's official clinician data lists Spencer W. Fast at 3 hospitals: Marshfield Medical Center - Weston, Reedsburg Area Medical Center and University of WI Hospitals & Clinics Authority. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Spencer W. Fast see patients?
Medicare's clinician data lists 2 practice locations, including Marshfield, WI and Weston, WI. Call before your visit to confirm the address.
What is Spencer W. Fast's specialty?
Medicare lists Family Practice as the primary specialty.
Does Spencer W. Fast accept Medicare assignment?
Yes. Medicare's clinician data says Spencer W. Fast 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 Spencer W. Fast?
(715) 387-5511, as listed in official Medicare / NPI Registry data.
What is Spencer W. Fast's NPI number?
1306990429. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Spencer W. Fast works

Medicare's Facility Affiliation Data lists Spencer W. Fast at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Spencer W. Fast is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Spencer W. Fast as a member of this group (CMS data updated 2026-10-02).

  • MCHS Hospitals Inc1,197 clinicians in the group

Specialties

Find other Family Practice doctors in Wisconsin →

Other family doctors in Marshfield

Clinicians with the same Medicare primary specialty in Marshfield, WI — not a recommendation.

All family doctors in Marshfield →

Clinician information

CredentialMD
Medical schoolMedical College Of Wisconsin
Graduation year2005
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1306990429
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. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  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