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

Dr. John Byron Williams, MD

Individual provider Gastroenterology Physician · NPI 1265516421

Dr. John Byron Williams, MD is a Gastroenterology in Madison, Wisconsin. Graduated from Saint Louis University School of Medicine in 2000, 26 years ago. Practices with University of Wisconsin Medical Foundation Inc, a 2,536-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Wisconsin.

Years since qualifying
26
Trained at
Saint Louis University School of Medicine
Licensed in
WI
In the registry since
2006
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

20 S Park St Ste 207
Madison, WI 53715-1348
Phone: (608) 287-2680
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Gastroenterology Physician (primary) Taxonomy 207RG0100X · Licence 43694-020 (WI)

Record details

NPI number1265516421
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedOctober 24, 2006
Last updated in NPPESJanuary 27, 2021
Certification dateJanuary 27, 2021
Mailing address20 S Park St, Suite 207, Madison, WI 53715-1348

Medicare enrollment

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

Medicare specialtyGASTROENTEROLOGY
Medical schoolSAINT LOUIS UNIVERSITY SCHOOL OF MEDICINE
Graduated 2000 (26 years in practice)
Group practice University Of Wisconsin Medical Foundation Inc — 2536 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

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