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Nephrology

William S. Asch, MD

Works at hospitals in Bridgeport, CT · Greenwich, CT · New London, CT … · Connecticut

Summary

William S. Asch, MD (Nephrology) is listed by Medicare at 5 hospitals in Bridgeport, CT, Greenwich, CT and New London, CT and other places. NPI 1003933326. 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 S. Asch, 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

NephrologyPrimary specialty
YesAccepts Medicare assignment
YesOffers telehealth
25Years since medical school (graduated 2001)
State University Of New York At Stony Brook, School Of MedicineMedical school
MaleGender (as listed)
Yale UniversityGroup practice

Quick answers

Which hospitals does William S. Asch work at?
Medicare's official clinician data lists William S. Asch at 5 hospitals: Bridgeport Hospital, Greenwich Hospital Association -, Lawrence & Memorial Hospital, St Francis Hospital & Medical Center and Yale-New Haven Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
Where does William S. Asch see patients?
Medicare's clinician data lists 3 practice locations, including New Haven, CT. Call before your visit to confirm the address.
What is William S. Asch's specialty?
Medicare lists Nephrology as the primary specialty.
Does William S. Asch accept Medicare assignment?
Yes. Medicare's clinician data says William S. Asch 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.
Does William S. Asch offer telehealth?
Medicare's clinician data says William S. Asch offers telehealth services. Ask the office which visits can be done by video or phone.
What is the phone number for William S. Asch?
(203) 785-2140, as listed in official Medicare / NPI Registry data.
What is William S. Asch's NPI number?
1003933326. 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 S. Asch works

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

Group practices

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

  • Yale University2,645 clinicians in the group

Specialties

Find other Nephrology doctors in Connecticut →

Other nephrologists in New Haven

Clinicians with the same Medicare primary specialty in New Haven, CT — not a recommendation.

All nephrologists in New Haven →

Clinician information

CredentialMD
Medical schoolState University Of New York At Stony Brook, School Of Medicine
Graduation year2001
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1003933326
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