Quick answers
- Which hospitals does Mallory Williams work at?
- Medicare's official clinician data lists Mallory Williams at 2 hospitals: John H Stroger Jr Hospital and University of Toledo Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Mallory Williams see patients?
- Medicare's clinician data lists 1 practice location in Chicago, IL. Call before your visit to confirm the address.
- What is Mallory Williams's specialty?
- Medicare lists General Surgery as the primary specialty.
- Does Mallory Williams accept Medicare assignment?
- Yes. Medicare's clinician data says Mallory 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 Mallory Williams?
- (312) 633-7292, as listed in official Medicare / NPI Registry data.
- What is Mallory Williams's NPI number?
- 1669488003. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Mallory Williams works
Medicare's Facility Affiliation Data lists Mallory Williams at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- John H Stroger Jr HospitalChicago, IL · Acute Care Hospital · CCN 140124
- University of Toledo Medical CenterToledo, OH · Acute Care Hospital · CCN 360048
Practice locations
Addresses where Mallory Williams is enrolled with Medicare (CMS data updated 2026-10-02).
- 1901 W Harrison StChicago, IL 60612 (312) 633‑7292
Group practices
Medicare enrollment lists Mallory Williams as a member of this group (CMS data updated 2026-10-02).
- Cook County788 clinicians in the group
Specialties
- General Surgeryprimary
Other general surgeons in Chicago
Clinicians with the same Medicare primary specialty in Chicago, IL — not a recommendation.
Clinician information
| Graduation year | 1999 |
|---|---|
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1669488003 |
| 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 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- 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