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Anesthesiology

Mark Williams, MD

Works at hospitals in Phoenix, AZ · Richardson, TX · Arizona, Texas

Summary

Mark Williams, MD (Anesthesiology) is listed by Medicare at 2 hospitals in Phoenix, AZ and Richardson, TX. NPI 1679505440. 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 Mark Williams, 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
40Years since medical school (graduated 1986)
MaleGender (as listed)
U S Anesthesia Partners of Texas, PAGroup practice

Quick answers

Which hospitals does Mark Williams work at?
Medicare's official clinician data lists Mark Williams at 2 hospitals: Honor Health John C. Lincoln Medical Center and Methodist Richardson Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Mark Williams see patients?
Medicare's clinician data lists 1 practice location in Richardson, TX. Call before your visit to confirm the address.
What is Mark Williams's specialty?
Medicare lists Anesthesiology as the primary specialty.
Does Mark Williams accept Medicare assignment?
Yes. Medicare's clinician data says Mark Williams 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 Mark Williams?
(469) 204-0702, as listed in official Medicare / NPI Registry data.
What is Mark Williams's NPI number?
1679505440. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Mark Williams works

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

Group practices

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

  • U S Anesthesia Partners of Texas, PA2,752 clinicians in the group

Specialties

Find other Anesthesiology doctors in Texas →

Other anesthesiologists in Richardson

Clinicians with the same Medicare primary specialty in Richardson, TX — not a recommendation.

All anesthesiologists in Richardson →

Clinician information

CredentialMD
Graduation year1986
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1679505440
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