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STEPHEN WILLIAMS INTERNAL MEDICINE MD PC
NPI 1811699051
Internal Medicine in Troy, MI

Active since March 21, 2023CLIA 23D2281973 · Waiver
1800 W BIG BEAVER RD STE 150, TROY, MI 48084(248) 688-0917(248) 419-6123 Get Directions Write a Review

NPPES record last updated: May 1, 2026. Verified against the NPPES registry weekly; last sync: November 08, 2026.

Record update history: May 1, 2026, Nov 9, 2023, Mar 21, 2023 (3 updates tracked since 2023).

About Stephen Williams Internal Medicine Md Pc NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

STEPHEN WILLIAMS INTERNAL MEDICINE MD PC (NPI 1811699051) is a healthcare organization registered as an internal medicine in Troy, Michigan and active in the NPI registry since March 2023. The organization holds a CLIA Waiver certificate valid through May 15, 2027 and lists Stephen A Williams, Physician/owner, as its authorized official.

NPPES Registry Identity

NPI1811699051
Entity TypeOrganization
Primary Taxonomy207R00000X
Legal Business NameSTEPHEN WILLIAMS INTERNAL MEDICINE MD PC
Location Address1800 W BIG BEAVER RD STE 150Troy, MI 48084-3535
Mailing Address1800 W Big Beaver Rd Ste 150Troy, MI 48084-3535 · (248) 688-0917 · Fax (248) 419-6123
Phone(248) 688-0917
Fax(248) 419-6123
Organization SubpartNo
Authorized OfficialStephen A WilliamsPhysician/owner · (248) 207-6784
Enumeration DateMarch 21, 2023
Last NPPES UpdateMay 1, 20263 updates tracked since enumeration
NPPES CertifiedMay 1, 2026
✔ NPI 1811699051 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
1800 W BIG BEAVER RD STE 150, Troy, MI 48084
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Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Blue Care Network of Michigan, Blue Cross Blue Shield of Michigan Mutual Insurance Company.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Stephen Williams Internal Medicine Md Pc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 1 clinician reassigns Medicare billing to Stephen Williams Internal Medicine MD PC, which bills Medicare for the services this clinician delivers.

Clinician (1)

Stephen Williams, MD
Internal Medicine
NPI 1962464982
1639 E BIG BEAVER RD STE 202
Troy, MI 48083
(248) 606-4190
✔ PECOS✔ Accepts Medicare2.9 mi

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

CLIA Laboratory Certificates CMS CLIA

Laboratory certificates issued under the Clinical Laboratory Improvement Amendments (CLIA) program, which sets federal quality standards for human laboratory testing in the United States. There is no official CMS crosswalk between CLIA and NPI numbers; these certificates are associated with this NPI by matching facility names, locations and phone numbers in the CMS CLIA registry.

Certificate of Waiver 23D2281973

Stephen Williams Internal Medicine MD PC · Troy, MI
Active · expires May 15, 2027
CLIA Number23D2281973
Laboratory TypePhysician Office
Certificate Effective DateMay 16, 2025
Certificate Expiration DateMay 15, 2027
Laboratory DirectorStephen Williams
Laboratory Phone(248) 688-0917
Laboratory LocationStephen Williams Internal Medicine MD PC1800 W Big Beaver Road Suite 150, Troy, MI 48084
CLIA data matches this NPI record on: Address Name Phone
This certificate is issued to a laboratory to perform only waived tests.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Stephen Williams Internal Medicine MD PC's NPI number?

The NPI number for Stephen Williams Internal Medicine MD PC is 1811699051. It was assigned to this organization in the NPPES registry on March 21, 2023.

Where is Stephen Williams Internal Medicine MD PC located?

Stephen Williams Internal Medicine MD PC is located at 1800 W Big Beaver Rd Ste 150, Troy, MI 48084. The listed phone number is (248) 688-0917.

What is Stephen Williams Internal Medicine MD PC's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Stephen Williams Internal Medicine MD PC enrolled in Medicare?

Yes. Stephen Williams Internal Medicine MD PC is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Stephen Williams Internal Medicine MD PC?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Internal Medicine) reassigns their Medicare billing to Stephen Williams Internal Medicine MD PC. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Does Stephen Williams Internal Medicine MD PC hold a CLIA laboratory certificate?

Yes. A Certificate of Waiver (number 23D2281973) is associated with this NPI, valid through May 15, 2027. CLIA certificates authorize laboratory testing under the federal Clinical Laboratory Improvement Amendments program.

What insurance does Stephen Williams Internal Medicine MD PC accept?

Health plans from Blue Care Network of Michigan and Blue Cross Blue Shield of Michigan Mutual Insurance Company list Stephen Williams Internal Medicine MD PC as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Stephen Williams Internal Medicine MD PC was last updated on May 1, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.