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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. William C Tarr, D.C.

Chiropractor in Menlo Park, CA · enumerated 2007 · practices at Longs Drug Stores California LLC.

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

National Provider Identifier

1093841306

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Registry record

Entity type Individual (Type 1)
Name Dr. William C Tarr
Credential D.C.
Sex Male
Practice address Menlo Park, CA, 94025
Phone (650) 233-7333
Fax (650) 233-7330
Enumeration date Feb 23, 2007
Last updated in NPPES Nov 5, 2018

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

111N00000X Chiropractor Chiropractic Providers · License DC022181 (CA) Primary
DC · Doctor of Chiropractic: A licensed chiropractor focusing on musculoskeletal and nervous system disorders. About the DC credential

Other identifiers

Identifier Type State Issuer
P00291270 Other CA RAILROAD RETIREMENT BOARD

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 William Tarr?
The National Provider Identifier (NPI) for William Tarr is 1093841306, a Type 1 (individual) record in the CMS NPPES registry.
Where does William Tarr practice?
The practice location on file with NPPES is in Menlo Park, 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 2018-11-05.