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Anesthesiology

William Semanczuk, MD

Works at hospitals in Nyack, NY · New York

Summary

William Semanczuk, MD (Anesthesiology) is listed by Medicare at 1 hospital in Nyack, NY. NPI 1720061146. 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 William Semanczuk, 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
27Years since medical school (graduated 1999)
MaleGender (as listed)
North Shore - Lij Anesthesiology, PCGroup practice

Quick answers

Which hospitals does William Semanczuk work at?
Medicare's official clinician data lists William Semanczuk at 1 hospital: Nyack Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
Where does William Semanczuk see patients?
Medicare's clinician data lists 1 practice location in Nyack, NY. Call before your visit to confirm the address.
What is William Semanczuk's specialty?
Medicare lists Anesthesiology as the primary specialty.
Does William Semanczuk accept Medicare assignment?
Yes. Medicare's clinician data says William Semanczuk 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 William Semanczuk?
(914) 666-8866, as listed in official Medicare / NPI Registry data.
What is William Semanczuk's NPI number?
1720061146. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where William Semanczuk works

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

Group practices

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

  • North Shore - Lij Anesthesiology, PC1,003 clinicians in the group

Specialties

Find other Anesthesiology doctors in New York →

Other anesthesiologists in Nyack

Clinicians with the same Medicare primary specialty in Nyack, NY — not a recommendation.

All anesthesiologists in Nyack →

Clinician information

CredentialMD
Graduation year1999
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1720061146
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