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CYNTHIA WILLIAMS M.D. INC.
NPI 1205947686
Internal Medicine - Endocrinology, Diabetes & Metabolism in Torrance, CA

Active since August 31, 2006CLIA 05D0991301 · Waiver
23560 MADISON ST STE 103, TORRANCE, CA 90505(310) 325-9200(310) 325-9201 Get Directions Write a Review

NPPES record last updated: December 1, 2017. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Cynthia Williams M.d. Inc. NPPES

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

CYNTHIA WILLIAMS M.D. INC. (NPI 1205947686) is a healthcare organization registered as an endocrinology, diabetes & metabolism in Torrance, California and active in the NPI registry since August 2006. The organization holds a CLIA Waiver certificate valid through March 16, 2027 and lists Cynthia Williams, Owner, as its authorized official.

NPPES Registry Identity

NPI1205947686
Entity TypeOrganization
Primary Taxonomy207RE0101X
Legal Business NameCYNTHIA WILLIAMS M.D. INC.
Location Address23560 MADISON ST STE 103Torrance, CA 90505-4709
Mailing Address23560 Madison St Ste 103Torrance, CA 90505-4709 · (310) 325-9200 · Fax (310) 325-9201
Phone(310) 325-9200
Fax(310) 325-9201
Organization SubpartNo
Authorized OfficialCynthia WilliamsOwner · (310) 325-9200
Enumeration DateAugust 31, 2006
Last NPPES UpdateDecember 1, 2017
✔ NPI 1205947686 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Endocrinology, Diabetes & MetabolismAllopathic & Osteopathic Physicians
Taxonomy Code207RE0101X
Definition
An internist who concentrates on disorders of the internal (endocrine) glands such as the thyroid and adrenal glands. This specialist also deals with disorders such as diabetes, metabolic and nutritional disorders, obesity, pituitary diseases and menstrual and sexual problems.
23560 MADISON ST STE 103, Torrance, CA 90505
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Other Identifiers 1

Medicare ID-Type UnspecifiedG75853CA

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

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Cynthia Williams M.d. Inc. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Medicare Revalidation Due Date

Revalidation due by March 31, 2027

Medicare-enrolled providers and suppliers confirm their enrollment information with CMS on a set cycle, every 5 years for most and every 3 years for medical equipment suppliers. CMS sets the due date for each enrollment.

StateEnrollment IDDue date
StateCaliforniaEnrollment IDO20061016000309Non-DME Part B · Clinic/Group PracticeDue dateMarch 31, 2027
Source: CMS Revalidation Due Date List, October 2026 release.

Clinicians Billing Medicare Through This Organization

2

Medicare enrollment records show 2 clinicians reassign Medicare billing to Cynthia Williams M.D. Inc., which bills Medicare for the services they deliver. Of these, 2 practice at this address. They are listed nearest first.

Clinicians, nearest first (2)

David Weiss, M.D.
Internal Medicine
NPI 1609958289
23560 MADISON ST STE 103
Torrance, CA 90505
(310) 325-9200
✔ PECOSSame address
Cynthia Williams, M.D.
Endocrinology
NPI 1265485049
23560 MADISON ST. SUITE 103
Torrance, CA 90505
(310) 325-9200
✔ PECOSSame address

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 05D0991301

Cynthia L Williams MD Inc · Torrance, CA
Active · expires Mar 16, 2027
CLIA Number05D0991301
Laboratory TypeIndependent
Certificate Effective DateMarch 17, 2025
Certificate Expiration DateMarch 16, 2027
Laboratory DirectorCynthia L. Williams
Laboratory Phone(310) 325-9200
Laboratory LocationCynthia L Williams MD Inc23560 Madison St Ste 103, Torrance, CA 90505
CLIA data matches this NPI record on: Address 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 Cynthia Williams M.D. Inc.'s NPI number?

The NPI number for Cynthia Williams M.D. Inc. is 1205947686. It was assigned to this organization in the NPPES registry on August 31, 2006.

Where is Cynthia Williams M.D. Inc. located?

Cynthia Williams M.D. Inc. is located at 23560 Madison St Ste 103, Torrance, CA 90505. The listed phone number is (310) 325-9200.

What is Cynthia Williams M.D. Inc.'s specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Endocrinology, Diabetes & Metabolism, with taxonomy code 207RE0101X.

Is Cynthia Williams M.D. Inc. enrolled in Medicare?

Yes. Cynthia Williams M.D. Inc. is registered in the Medicare PECOS enrollment system.

When is Cynthia Williams M.D. Inc.'s Medicare revalidation due?

According to the CMS Revalidation Due Date List (October 2026 release), the Medicare Non-DME Part B enrollment for this organization (California, Clinic/Group Practice) is due for revalidation by March 31, 2027. Medicare providers and suppliers revalidate their enrollment every 5 years, and medical equipment suppliers every 3 years. Confirm current requirements with your Medicare Administrative Contractor.

How many clinicians bill Medicare through Cynthia Williams M.D. Inc.?

According to the CMS Revalidation Reassignment List (October 2026 release), 2 clinicians reassign their Medicare billing to Cynthia Williams M.D. Inc., in Endocrinology and Internal Medicine. 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. Of these, 2 practice at this address. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Does Cynthia Williams M.D. Inc. hold a CLIA laboratory certificate?

Yes. A Certificate of Waiver (number 05D0991301) is associated with this NPI, valid through March 16, 2027. CLIA certificates authorize laboratory testing under the federal Clinical Laboratory Improvement Amendments program.

When was this NPI record last updated?

The NPPES record for Cynthia Williams M.D. Inc. was last updated on December 1, 2017. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 years 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.