Quick answers
- Which hospitals does William S. Tan work at?
- Medicare's official clinician data lists William S. Tan at 5 hospitals: Advocate Christ Hospital & Medical Center, Advocate Trinity Hospital, Franciscan Health Munster, Franciscan Health Olympia & Chicago Heights and Ingalls Memorial Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does William S. Tan see patients?
- Medicare's clinician data lists 1 practice location in Olympia Fields, IL. Call before your visit to confirm the address.
- What is William S. Tan's specialty?
- Medicare lists Family Practice as the primary specialty.
- Does William S. Tan accept Medicare assignment?
- Yes. Medicare's clinician data says William S. Tan 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 S. Tan?
- (708) 283-8300, as listed in official Medicare / NPI Registry data.
- What is William S. Tan's NPI number?
- 1891112306. 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. Tan works
Medicare's Facility Affiliation Data lists William S. Tan at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Advocate Christ Hospital & Medical CenterOak Lawn, IL · Acute Care Hospital · CCN 140208
- Advocate Trinity HospitalChicago, IL · Acute Care Hospital · CCN 140048
- Franciscan Health MunsterMunster, IN · Acute Care Hospital · CCN 150165
- Franciscan Health Olympia & Chicago HeightsOlympia Fields, IL · Acute Care Hospital · CCN 140172
- Ingalls Memorial HospitalHarvey, IL · Acute Care Hospital · CCN 140191
Practice locations
Addresses where William S. Tan is enrolled with Medicare (CMS data updated 2026-10-02).
- 20060 Governors Dr, Suite 204Olympia Fields, IL 60461 (708) 283‑8300
Specialties
- Family Practiceprimary
Other family doctors in Illinois
Clinicians with the same Medicare primary specialty in Illinois — not a recommendation.
Clinician information
| Credential | DO |
|---|---|
| Medical school | Nova Southeastern College Of Osteo Medicine |
| Graduation year | 2013 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1891112306 |
| 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