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Mrs. Cornelia B Masak, RN, APNP

Mrs. Cornelia B Masak is a Nurse Practitioner provider (Nurse Practitioner) practicing in Appleton, WI, registered in the NPPES registry with NPI 1740319516 since 2007. The credential RN stands for Registered Nurse.

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NPI 1740319516
Entity type Individual (Type 1)
Name Mrs. Cornelia B Masak
Credential RN, APNP
Sex Female
Practice address 1818 N MEADE ST, Appleton, WI, 54911
Phone 9207494000
Fax 9207494015
Enumeration date 2007-03-05
Last updated in NPPES 2022-11-23

Taxonomy & licenses

Taxonomy code Specialty Primary License State
363L00000X Nurse Practitioner Primary 93688 WI

RN — Registered Nurse: A nurse who completed an accredited nursing program and passed the NCLEX-RN licensure exam. About the RN credential

Copy-ready billing details
Provider: Cornelia Masak, RN, APNP
NPI: 1740319516
Taxonomy: 363L00000X (Nurse Practitioner)
Address: 1818 N MEADE ST, Appleton, WI, 54911

Other providers at this practice address

NPI Name Type Specialty Location
1588666853 Appleton Emergency Services S C Organization Emergency Medicine Physician Appleton, WI
1689679953 Michael Hooker Individual Hospitalist Physician Appleton, WI
1346249323 Honnie Bermas Individual Surgery Physician Appleton, WI
1306846894 Steven Mcintyre Individual Emergency Medical Services (Emergency Medicine) Physician Appleton, WI
1194725879 Cyril Walsh Individual Emergency Medical Services (Emergency Medicine) Physician Appleton, WI
1558361238 Sharon Thorson Individual Family Nurse Practitioner Appleton, WI
1902806698 Brad Sandleback Individual Emergency Medical Services (Emergency Medicine) Physician Appleton, WI
1831199439 Craig Quandt-Walle Individual Medical Physician Assistant Appleton, WI

Verify this record

Cross-check NPI 1740319516 against the authoritative CMS record: view Mrs. Cornelia B Masak 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

What is the NPI number for Cornelia Masak?
The National Provider Identifier (NPI) for Cornelia Masak is 1740319516, a Type 1 (individual) record in the CMS NPPES registry.
Where does Cornelia Masak practice?
The practice location on file with NPPES is in Appleton, WI. Providers can have multiple locations; NPPES lists the primary practice address.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2022-11-23.