Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

William Bayer, MD

Individual provider Endocrinology, Diabetes & Metabolism Physician · NPI 1528162898

William Bayer, MD is an Endocrinology in Carol Stream, Illinois. Graduated from Loyola University of Chicago, Stritch School of Medicine in 1986, 40 years ago. Practices with Central Dupage Physician Group, a 1,094-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Illinois.

Years since qualifying
40
Trained at
Loyola University of Chicago, Stritch School of Medicine
Licensed in
IL
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Practice location Address checks out

501 Thornhill Dr
Carol Stream, IL 60188-2793
Phone: (630) 668-3210
Fax: (630) 668-3505
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Endocrinology, Diabetes & Metabolism Physician (primary) Taxonomy 207RE0101X · Licence 036077734 (IL)

Record details

NPI number1528162898
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedSeptember 8, 2006
Last updated in NPPESMarch 25, 2015
Mailing address501 Thornhill Dr, Carol Stream, IL 60188-2793

Medicare enrollment

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

Medicare specialtyENDOCRINOLOGY
Also practisesINTERNAL MEDICINE
Medical schoolLOYOLA UNIVERSITY OF CHICAGO, STRITCH SCHOOL OF MEDICINE
Graduated 1986 (40 years in practice)
Group practice Central Dupage Physician Group — 1094 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations6 on file with Medicare

Other providers in Carol Stream