Quick answers
- Does Zachary Johannesson accept Medicare assignment?
- Yes. Medicare's clinician data says Zachary Johannesson 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 Zachary Johannesson see?
- In 2024, CMS data shows 127 Original Medicare patients and 203 services for Zachary Johannesson. This counts Original Medicare only and measures volume, not quality.
- What is Zachary Johannesson's NPI number?
- 1184203663. 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 Zachary Johannesson, 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 patients | 127 |
|---|---|
| Services billed to Medicare | 203 |
| Different services or procedures | 8 |
| Participating Medicare provider | Yes |
| Average age of these patients | 75 |
Most frequent services
- Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only (93010)91 services
- Emergency department visit with high level of medical decision making (99285)82 services
- Emergency department visit with moderate level of medical decision making (99284)17 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%
- Arthritis45%
- Ischemic heart disease43%
- Diabetes42%
- Heart failure35%
Hospitals where Zachary Johannesson works
Medicare's Facility Affiliation Data lists Zachary Johannesson 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.
- Canton-Potsdam HospitalPotsdam, NY · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 330197
- Gouverneur HospitalGouverneur, NY · Critical Access Hospital · Emergency services: listed by Medicare · CCN 331315
Practice locations
Addresses where Zachary Johannesson is enrolled with Medicare (CMS data updated October 2, 2026).
- 50 Leroy StPotsdam, NY 13676 (315) 265‑3300
Group practices
Medicare enrollment lists Zachary Johannesson as a member of this group (CMS data updated October 2, 2026).
- Canton-Potsdam Hospital252 clinicians in the group
Specialties
- Emergency Medicineprimary
Other emergency medicine doctors in Potsdam
Clinicians with the same Medicare primary specialty in Potsdam, NY — not a recommendation.
Other clinicians in Canton-Potsdam Hospital
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Medical school | Ohio State University College Of Medicine |
|---|---|
| Graduation year | 2024 (2 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1184203663 |
| 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 October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- 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