Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Dr. Stephen John Mendak, MD
Surgery Physician in Elmhurst, IL · enumerated 2006.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1154419257
See something wrong? Report a correction
Registry record
Entity type Individual (Type 1)
Name Dr. Stephen John Mendak
Credential MD
Sex Male
Practice address 340 W Butterfield Rd, 1d, Elmhurst, IL, 60126
Phone (630) 279-5701
Fax (630) 279-5144
Enumeration date Oct 11, 2006
Last updated in NPPES Jul 8, 2007
Taxonomy & licenses
MD — Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure.
About the MD credential
What is an NPI number?
A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes — even if the provider moves or changes specialty.
Frequently asked questions
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Stephen Mendak?
Stephen Mendak is registered in NPPES with the primary taxonomy of Surgery Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Other providers at this practice address
Browse all → Victoria Grannan-Manchen General Practice Dentistry · Elmhurst, IL NPI 1124132279 David M. Karas, D.D.S. General Practice Dentistry · Elmhurst, IL NPI 1306972260 Orthotec Surgery Center, Inc Ambulatory Surgical Clinic/Center · Elmhurst, IL NPI 1205234143 Dearbone Counseling Center, Inc Mental Health Counselor · Elmhurst, IL NPI 1902333651 Through the Woods Pllc Mental Health Counselor · Elmhurst, IL NPI 1063121465 Evie Life Psychiatry LLC Psychiatric/Mental Health Nurse Practitioner · Elmhurst, IL NPI 1306614664 Rima Muhsen Mental Health Counselor · Elmhurst, IL NPI 1790553741 Wills Therapy Services, LLC Mental Health Counselor · Elmhurst, IL NPI 1700627288
Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.