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Dr. Dennis Whittier Hartman, O.D.

Optometrist in Merced, CA · enumerated 2006 · practices at Kenneth R Grossman MD Inc.

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

National Provider Identifier

1922078294

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Registry record

Entity type Individual (Type 1)
Name Dr. Dennis Whittier Hartman
Credential O.D.
Sex Male
Practice address 580 Collins Dr, Merced, CA, 95348
Phone (209) 383-0989
Fax (209) 383-6836
Enumeration date Jan 26, 2006
Last updated in NPPES Jan 11, 2023

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License 9253T (CA) 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
9253T Other CA STATE LICENSE

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 Dennis Hartman?
The National Provider Identifier (NPI) for Dennis Hartman is 1922078294, a Type 1 (individual) record in the CMS NPPES registry.
Where does Dennis Hartman practice?
The practice location on file with NPPES is in Merced, CA. 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 2023-01-11.