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Dr. William Francis Owen Jr., M.D.

Internal Medicine Physician in San Francisco, CA · enumerated 2005.

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

National Provider Identifier

1154323483

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Registry record

Entity type Individual (Type 1)
Name Dr. William Francis Owen Jr.
Credential M.D.
Sex Male
Practice address 45 Castro St, Ste 402, San Francisco, CA, 94114
Phone (415) 861-2400
Fax (415) 861-8733
Enumeration date May 31, 2005
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License G31385 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
00G313850 Medicaid CA -

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 William Owen practice?
The practice location on file with NPPES is in San Francisco, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for William Owen?
The National Provider Identifier (NPI) for William Owen is 1154323483, a Type 1 (individual) record in the CMS NPPES registry.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.