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Mary E Siemek, RD, CDE

Registered Dietitian in Neenah, WI · enumerated 2007.

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

National Provider Identifier

1275663882

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Registry record

Entity type Individual (Type 1)
Name Mary E Siemek
Credential RD, CDE
Sex Female
Practice address 130 2nd St, Neenah, WI, 54956
Phone (920) 729-2046
Enumeration date Mar 6, 2007
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

133V00000X Registered Dietitian Dietary & Nutritional Service Providers · License 198-029 (WI) Primary
RD · Registered Dietitian: A nutrition professional credentialed by the Commission on Dietetic Registration. About the RD 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.

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Frequently asked questions

What is the NPI number for Mary Siemek?
The National Provider Identifier (NPI) for Mary Siemek is 1275663882, a Type 1 (individual) record in the CMS NPPES registry.
Where does Mary Siemek practice?
The practice location on file with NPPES is in Neenah, WI. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.