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WINNETKA AVENUE PHYSICIANS, SC
NPI 1346633971
Internal Medicine in Winnetka, IL

Active since March 06, 2015CLIA 14D1065376 · Waiver
525 WINNETKA AVE, WINNETKA, IL 60093(847) 501-5060(847) 501-4063 Get Directions Write a Review

NPPES record last updated: January 26, 2016. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Winnetka Avenue Physicians, Sc NPPES

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

WINNETKA AVENUE PHYSICIANS, SC (NPI 1346633971) is a healthcare organization registered as an internal medicine in Winnetka, Illinois and active in the NPI registry since March 2015. The organization holds a CLIA Waiver certificate valid through February 27, 2027 and lists Thomas Stern, Physician/owner, as its authorized official.

NPPES Registry Identity

NPI1346633971
Entity TypeOrganization
Primary Taxonomy207R00000X
Legal Business NameWINNETKA AVENUE PHYSICIANS, SC
Location Address525 WINNETKA AVEWinnetka, IL 60093-4050
Mailing Address2215 Sanders Rd, Ste 105Northbrook, IL 60062-6126 · (224) 330-6300 · Fax (224) 330-6325
Phone(847) 501-5060
Fax(847) 501-4063
Organization SubpartNo
Authorized OfficialThomas SternPhysician/owner · (847) 501-4060
Enumeration DateMarch 6, 2015
Last NPPES UpdateJanuary 26, 2016
✔ NPI 1346633971 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.
525 WINNETKA AVE, Winnetka, IL 60093
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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

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Winnetka Avenue Physicians, Sc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

2

Medicare enrollment records show 2 clinicians reassign Medicare billing to Winnetka Avenue Physicians, Sc, which bills Medicare for the services they deliver. Of these, 2 practice at this address. They are listed nearest first.

Clinicians, nearest first (2)

Roman Mandzij, DO
Internal Medicine
NPI 1841239902
525 WINNETKA AVE
Winnetka, IL 60093
(847) 501-4060
✔ PECOS✔ Accepts MedicareSame address
Thomas Stern, MD
Internal Medicine
NPI 1477592665
525 WINNETKA AVE
Winnetka, IL 60093
(847) 501-4060
✔ PECOS✔ Accepts MedicareSame 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 14D1065376

Winnetka Avenue Physicians S C · Winnetka, IL
Active · expires Feb 27, 2027
CLIA Number14D1065376
Laboratory TypePhysician Office
Certificate Effective DateFebruary 28, 2025
Certificate Expiration DateFebruary 27, 2027
Laboratory DirectorRoman Mandzij
Laboratory Phone(847) 501-4060
Laboratory LocationWinnetka Avenue Physicians S C525 Winnetka Ave, Winnetka, IL 60093
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 Winnetka Avenue Physicians, Sc's NPI number?

The NPI number for Winnetka Avenue Physicians, Sc is 1346633971. It was assigned to this organization in the NPPES registry on March 6, 2015.

Where is Winnetka Avenue Physicians, Sc located?

Winnetka Avenue Physicians, Sc is located at 525 Winnetka Ave, Winnetka, IL 60093. The listed phone number is (847) 501-5060.

What is Winnetka Avenue Physicians, Sc's specialty?

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

Is Winnetka Avenue Physicians, Sc enrolled in Medicare?

Yes. Winnetka Avenue Physicians, Sc is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Winnetka Avenue Physicians, Sc?

According to the CMS Revalidation Reassignment List (October 2026 release), 2 clinicians, all in Internal Medicine, reassign their Medicare billing to Winnetka Avenue Physicians, Sc. 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 Winnetka Avenue Physicians, Sc hold a CLIA laboratory certificate?

Yes. A Certificate of Waiver (number 14D1065376) is associated with this NPI, valid through February 27, 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 Winnetka Avenue Physicians, Sc was last updated on January 26, 2016. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 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.