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Emergency Medicine

Matthew J. Larsen, MD

Works at hospitals in Twin Falls, ID · Idaho

Summary

Dr. Matthew J. Larsen, MD is an emergency medicine doctor at 746 N College Rd, Twin Falls, ID 83301. Accepts Medicare assignment. In 2024, Matthew J. Larsen had 113 Original Medicare patients and 121 services. NPI 1194916049. 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: 746 N College Rd, Twin Falls, ID 83301 · Directions
  • Medicare: Accepts Medicare assignment
  • Hospital: St Lukes Magic Valley Medical Center
  • Group practice: St Lukes Clinic LLC
  • Medical school: University Of Utah School Of Medicine · graduated 1999 (27 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Matthew J. Larsen, 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 Matthew J. Larsen accept Medicare assignment?
Yes. Medicare's clinician data says Matthew J. Larsen 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 Matthew J. Larsen see?
In 2024, CMS data shows 113 Original Medicare patients and 121 services for Matthew J. Larsen. This counts Original Medicare only and measures volume, not quality.
What is Matthew J. Larsen's NPI number?
1194916049. 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 Matthew J. Larsen, 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 patients113
Services billed to Medicare121
Different services or procedures11
Participating Medicare providerYes
Average age of these patients75

Most frequent services

  1. Emergency department visit with high level of medical decision making (99285)65 services
  2. Emergency department visit with moderate level of medical decision making (99284)44 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 cholesterol66%
  • Diabetes45%
  • Arthritis44%
  • Anxiety39%
  • Depression37%

Hospitals where Matthew J. Larsen works

Medicare's Facility Affiliation Data lists Matthew J. Larsen 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 Matthew J. Larsen is enrolled with Medicare (CMS data updated October 2, 2026).

  • 746 N College RdTwin Falls, ID 83301

Group practices

Medicare enrollment lists Matthew J. Larsen as a member of this group (CMS data updated October 2, 2026).

  • St Lukes Clinic LLC316 clinicians in the group

Specialties

Find other Emergency Medicine doctors in Idaho →

Other emergency medicine doctors in Twin Falls

Clinicians with the same Medicare primary specialty in Twin Falls, ID — not a recommendation.

All emergency medicine doctors in Twin Falls →

Other clinicians in St Lukes Clinic LLC

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

Clinician information

CredentialMD
Medical schoolUniversity Of Utah School Of Medicine
Graduation year1999 (27 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1194916049
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