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Dr. Donald David Schwellenbach, O.D.

Optometrist in Yuba City, CA · enumerated 2007 · practices at Ronald A Kalayta Medical Corporation.

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

National Provider Identifier

1013123603

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Registry record

Entity type Individual (Type 1)
Name Dr. Donald David Schwellenbach
Credential O.D.
Sex Male
Practice address 901 Maple Ave, Yuba City, CA, 95991
Phone (530) 674-8170
Fax (530) 674-5728
Enumeration date May 14, 2007
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License OPT00007872 (CA) Primary
OD · Doctor of Optometry: A licensed optometrist providing primary vision care, eye exams, and corrective lenses. About the OD 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

Where does Donald Schwellenbach practice?
The practice location on file with NPPES is in Yuba City, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Donald Schwellenbach?
The National Provider Identifier (NPI) for Donald Schwellenbach is 1013123603, 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 2007-07-08.