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Amy Tesar, DO

Internal Medicine Physician in Mason City, IA · enumerated 2006.

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

National Provider Identifier

1841307477

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Registry record

Entity type Individual (Type 1)
Name Amy Tesar
Credential DO
Sex Female
Practice address 1000 4th St Sw, Mason City, IA, 50401
Phone (641) 428-6999
Fax (641) 428-6678
Enumeration date Aug 23, 2006
Last updated in NPPES Jul 14, 2025

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 03524 (IA) Secondary
208M00000X Hospitalist Physician Allopathic & Osteopathic Physicians · License 3524 (IA) Secondary
207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License DO-03524 (IA) Primary
DO · Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO credential

Other identifiers

Identifier Type State Issuer
0480475 Medicaid IA -
04350 Other IA WELLMARK

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

Where does Amy Tesar practice?
The practice location on file with NPPES is in Mason City, IA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Amy Tesar?
The National Provider Identifier (NPI) for Amy Tesar is 1841307477, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-07-14.