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Anesthesiology

Zachary Fleissner, DO

Works at hospitals in Jacksonville, FL · Florida

Summary

Zachary Fleissner, DO (Anesthesiology) is listed by Medicare at 1 hospital in Jacksonville, FL. NPI 1033773494. 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 Zachary Fleissner, 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

AnesthesiologyPrimary specialty
YesAccepts Medicare assignment
7Years since medical school (graduated 2019)
Lake Erie College Of Osteopathic Medicine, ErieMedical school
MaleGender (as listed)
Mayo Clinic JacksonvilleGroup practice

Quick answers

Which hospitals does Zachary Fleissner work at?
Medicare's official clinician data lists Zachary Fleissner at 1 hospital: Mayo Clinic. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Zachary Fleissner see patients?
Medicare's clinician data lists 1 practice location in Jacksonville, FL. Call before your visit to confirm the address.
What is Zachary Fleissner's specialty?
Medicare lists Anesthesiology as the primary specialty.
Does Zachary Fleissner accept Medicare assignment?
Yes. Medicare's clinician data says Zachary Fleissner 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 Zachary Fleissner?
(904) 953-2000, as listed in official Medicare / NPI Registry data.
What is Zachary Fleissner's NPI number?
1033773494. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Zachary Fleissner works

Medicare's Facility Affiliation Data lists Zachary Fleissner 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 Zachary Fleissner is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Zachary Fleissner as a member of this group (CMS data updated 2026-10-02).

  • Mayo Clinic Jacksonville1,615 clinicians in the group

Specialties

Find other Anesthesiology doctors in Florida →

Other anesthesiologists in Jacksonville

Clinicians with the same Medicare primary specialty in Jacksonville, FL — not a recommendation.

All anesthesiologists in Jacksonville →

Clinician information

CredentialDO
Medical schoolLake Erie College Of Osteopathic Medicine, Erie
Graduation year2019
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1033773494
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