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Dr. Marcellus Tin-Yau Chow, OD

Optometrist in San Francisco, CA · enumerated 2006 · practices at Andrew Calman.

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

National Provider Identifier

1194890012

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Registry record

Entity type Individual (Type 1)
Name Dr. Marcellus Tin-Yau Chow
Credential OD
Sex Male
Practice address 3201 Mission St, San Francisco, CA, 94110
Phone (415) 648-3600
Fax (415) 648-0719
Enumeration date Nov 24, 2006
Last updated in NPPES Dec 30, 2021

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License 12033T (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

What is the NPI number for Marcellus Chow?
The National Provider Identifier (NPI) for Marcellus Chow is 1194890012, a Type 1 (individual) record in the CMS NPPES registry.
Where does Marcellus Chow practice?
The practice location on file with NPPES is in San Francisco, 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 2021-12-30.