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Dennis D Tieszen, OD

Optometrist in Waterloo, IA · enumerated 2007 · practices at Iowa Eyecare Associates PC.

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

National Provider Identifier

1952452831

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Registry record

Entity type Individual (Type 1)
Name Dennis D Tieszen
Credential OD
Sex Male
Practice address 999 Home Plz, Suite 100, Waterloo, IA, 50701
Phone (319) 236-0815
Enumeration date Jan 16, 2007
Last updated in NPPES Dec 22, 2009

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License 01790 (IA) Primary
OD · Doctor of Optometry: A licensed optometrist providing primary vision care, eye exams, and corrective lenses. About the OD credential

Other identifiers

Identifier Type State Issuer
0117267 Medicaid IA -
18418 Other IA BLUE CROSS BLUE SHIELD
410030429 Other IA MEDICARE ID
CG4244 Other IA MEDICARE ID

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 Dennis Tieszen practice?
The practice location on file with NPPES is in Waterloo, IA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Dennis Tieszen?
The National Provider Identifier (NPI) for Dennis Tieszen is 1952452831, 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 2009-12-22.