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Dr. Michael Thomas Oneill, DDS

General Practice Dentistry in San Ramon, CA · enumerated 2007.

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

National Provider Identifier

1326261025

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Registry record

Entity type Individual (Type 1)
Name Dr. Michael Thomas Oneill
Credential DDS
Sex Male
Practice address 525 Bollinger Canyon Way, Suite 105, San Ramon, CA, 94582
Phone (925) 735-3838
Fax (925) 735-3866
Enumeration date Apr 11, 2007
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

1223G0001X General Practice Dentistry Dental Providers · License 27814 (CA) Primary
DDS · Doctor of Dental Surgery: A licensed dentist; DDS and DMD are equivalent dental degrees. About the DDS 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

Is NPI 1326261025 active?
Yes, as of the latest NPPES snapshot, NPI 1326261025 is active (record last updated 2007-07-08).
How do I verify Michael Oneill's NPI record?
Cross-check NPI 1326261025 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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