NPI Portal NPI Lookup & Verification

Dr. Stan L Markus, MD

Dr. Stan L Markus is a Surgery Physician provider (Surgery) practicing in Oconomowoc, WI, registered in the NPPES registry with NPI 1134103641 since 2005. The credential MD stands for Doctor of Medicine.

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NPI 1134103641
Entity type Individual (Type 1)
Name Dr. Stan L Markus
Credential MD
Sex Male
Practice address 888 THACKERAY TRL STE 103, Oconomowoc, WI, 53066
Phone 2625671499
Fax 2625674502
Enumeration date 2005-11-30
Last updated in NPPES 2017-11-29

Taxonomy & licenses

Taxonomy code Specialty Primary License State
208C00000X Colon & Rectal Surgery Physician Secondary 28258 WI
208600000X Surgery Physician Primary 28258 WI

MD — Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
30821400 Medicaid WI
Copy-ready billing details
Provider: Stan Markus, MD
NPI: 1134103641
Taxonomy: 208600000X (Surgery Physician)
Address: 888 THACKERAY TRL STE 103, Oconomowoc, WI, 53066

Other providers at this practice address

NPI Name Type Specialty Location
1508825605 Eric Elliot Individual Physician Assistant Oconomowoc, WI
1710946132 Cynthia Pangallo Individual Surgery Physician Oconomowoc, WI
1457311441 Emily Stoddard Individual Surgery Physician Oconomowoc, WI
1831862895 Allegiance Medical, Inc. Organization Internal Medicine Physician Oconomowoc, WI
1265230601 Primelife Health and Wellness Organization Integrative Medicine Physician Oconomowoc, WI

Verify this record

Cross-check NPI 1134103641 against the authoritative CMS record: view Dr. Stan L Markus on the official NPPES registry .

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. Read the full guide or validate an NPI number.

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 Stan Markus?
Stan Markus 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.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2017-11-29.