Medical emergency?Emergency? Call 911. Nearest emergency roomsNearest ERs

Nurse Practitioner

Amy M. Fellenz

Works at hospitals in Marshfield, WI · Wisconsin

Summary

Amy M. Fellenz is a nurse practitioner at 1000 N Oak Ave, Marshfield, WI 54449. Phone: (715) 387-5511. Accepts Medicare assignment. In 2024, Amy M. Fellenz had 162 Original Medicare patients and 277 services. NPI 1619534690. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

From official Medicare data

This page shows what Medicare's official clinician data says about Amy M. Fellenz, 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 Amy M. Fellenz accept Medicare assignment?
Yes. Medicare's clinician data says Amy M. Fellenz 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 Amy M. Fellenz see?
In 2024, CMS data shows 162 Original Medicare patients and 277 services for Amy M. Fellenz. This counts Original Medicare only and measures volume, not quality.
What is Amy M. Fellenz's NPI number?
1619534690. 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 Amy M. Fellenz, 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 patients162
Services billed to Medicare277
Different services or procedures30
Participating Medicare providerYes
Average age of these patients73

Most frequent services

  1. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)57 services
  2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)35 services
  3. Established patient office or other outpatient visit with straightforward medical decision making, if using time, 10 minutes or more (99212)27 services
  4. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)27 services
  5. Initial hospital care with straightforward or low level of medical decision making, per day, if using time, at least 40 minutes (99221)20 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 blood pressure75%
  • High cholesterol70%
  • Anxiety38%
  • Chronic kidney disease38%
  • Diabetes36%
  • Ischemic heart disease35%

Hospitals where Amy M. Fellenz works

Medicare's Facility Affiliation Data lists Amy M. Fellenz at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

Practice locations

Addresses where Amy M. Fellenz is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Amy M. Fellenz as a member of this group (CMS data updated October 2, 2026).

  • MCHS Hospitals Inc1,197 clinicians in the group

Specialties

Find other clinicians: Nurse Practitioner, Wisconsin →

Other nurse practitioners in Marshfield

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

All nurse practitioners in Marshfield →

Other clinicians in MCHS Hospitals Inc

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

Clinician information

Graduation year2019
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1619534690
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 October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians