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Emergency Medicine

Timothy W. Westlake, MD

Works at hospitals in Oconomowoc, WI · Waukesha, WI · Wisconsin

Summary

Dr. Timothy W. Westlake, MD is an emergency medicine doctor at 240 Maple Ave, Mukwonago, WI 53149. Phone: (262) 363-1900. Accepts Medicare assignment. In 2024, Timothy W. Westlake had 519 Original Medicare patients and 861 services. NPI 1184600447. 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.

  • Specialty: Emergency medicine doctor (Medicare lists Emergency Medicine)
  • Address: 240 Maple Ave, Mukwonago, WI 53149 · Directions (1 more location)
  • Phone: (262) 363‑1900
  • Medicare: Accepts Medicare assignment
  • Hospitals: Oconomowoc Memorial Hospital, Waukesha Memorial Hospital
  • Group practice: Emergency Medical Associates LLP
  • Medical school: Medical College Of Wisconsin · graduated 1995 (31 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Timothy W. Westlake, 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 Timothy W. Westlake accept Medicare assignment?
Yes. Medicare's clinician data says Timothy W. Westlake 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 Timothy W. Westlake see?
In 2024, CMS data shows 519 Original Medicare patients and 861 services for Timothy W. Westlake. This counts Original Medicare only and measures volume, not quality.
What is Timothy W. Westlake's NPI number?
1184600447. 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 Timothy W. Westlake, 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 patients519
Services billed to Medicare861
Different services or procedures28
Participating Medicare providerYes
Average age of these patients75

Most frequent services

  1. Emergency department visit with high level of medical decision making (99285)272 services
  2. Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only (93010)234 services
  3. Critical care, first 30-74 minutes (99291)160 services
  4. Emergency department visit with moderate level of medical decision making (99284)136 services
  5. Emergency department visit with low level of medical decision making (99283)16 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 cholesterol75%
  • Arthritis54%
  • Chronic kidney disease39%
  • Ischemic heart disease37%
  • Anxiety34%

Hospitals where Timothy W. Westlake works

Medicare's Facility Affiliation Data lists Timothy W. Westlake 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 Timothy W. Westlake is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Timothy W. Westlake as a member of this group (CMS data updated October 2, 2026).

  • Emergency Medical Associates LLP17 clinicians in the group

Specialties

Find other Emergency Medicine doctors in Wisconsin →

Other emergency medicine doctors in Mukwonago

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

All emergency medicine doctors in Mukwonago →

Other clinicians in Emergency Medical Associates LLP

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

Clinician information

CredentialMD
Medical schoolMedical College Of Wisconsin
Graduation year1995 (31 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1184600447
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