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Mark W Niedfeldt, MD, LLC

Family Medicine Physician in Mequon, WI · enumerated 2009 · authorized official Mark Niedfeldt, Owner.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1174764906

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Registry record

Entity type Organization (Type 2)
Legal business name Mark W Niedfeldt, MD, LLC
Practice address 10556 N Port Washington Rd, Ste 101, Mequon, WI, 53092
Phone (262) 643-4720
Fax (262) 643-4721
Enumeration date Mar 6, 2009
Last updated in NPPES Mar 6, 2009

Taxonomy & classification

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License 35201 (WI) Primary
207QS0010X Sports Medicine (Family Medicine) Physician Allopathic & Osteopathic Physicians · License 35201 (WI) Secondary

Authorized official

Name Mark Niedfeldt
Title Owner
Phone (262) 643-4720

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.

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Frequently asked questions

What is the NPI number for Mark W Niedfeldt, MD, LLC?
The NPI for Mark W Niedfeldt, MD, LLC is 1174764906, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for Mark W Niedfeldt, MD, LLC?
NPPES lists Mark Niedfeldt (Owner) as the authorized official for this organization.

Providers at this address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2009-03-06.