Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Michael Gregory Williams, MD

Individual provider Emergency Medicine Physician · NPI 1578561304

Michael Gregory Williams, MD practises Emergency Medicine in Southfield, Michigan. Graduated from University of Michigan Medical School in 1984, 42 years ago. Practices with Theoria Medical, a 342-clinician group and accepts Medicare assignment. Licensed in Michigan.

Years since qualifying
42
Trained at
University of Michigan Medical School
Licensed in
MI
In the registry since
2005
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

20411 W 12 Mile Rd Ste 102
Southfield, MI 48076-6404
Phone: (248) 905-3194
Fax: (248) 905-3548
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

General Practice Physician (primary) Taxonomy 208D00000X · Licence 4301049187 (MI)
Emergency Medicine Physician Taxonomy 207P00000X · Licence MW049187 (MI)

Record details

NPI number1578561304
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorYes
NPI enumeratedJuly 14, 2005
Last updated in NPPESJanuary 18, 2026
Certification dateJanuary 18, 2026

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyEMERGENCY MEDICINE
Medical schoolUNIVERSITY OF MICHIGAN MEDICAL SCHOOL
Graduated 1984 (42 years in practice)
Group practice Theoria Medical — 342 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients54
Services billed 172 a service is one billed item, such as a visit, a test or a procedure
Average patient age63

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician. Those with a page here are linked.

  • Medilodge of Grand Rapids Nursing home · Grand Rapids, MI · listed as United Church Homes Inc
  • Corewell Health Hospice & Palliative Care - West Michigan Hospice · Grand Rapids, MI

Colleagues at Theoria Medical

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 342 clinicians in the practice; 12 are shown here.

Other providers in Southfield