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Dr. William Arthur Brennan, D.D.S.

Periodontics in Green Bay, WI · enumerated 2006.

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

National Provider Identifier

1013931823

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Registry record

Entity type Individual (Type 1)
Name Dr. William Arthur Brennan
Credential D.D.S.
Sex Male
Practice address 430 Main St, Green Bay, WI, 54301
Fax (920) 431-1715
Enumeration date Jul 26, 2006
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

1223P0300X Periodontics Dental Providers · License 0004656-015 (WI) Primary
DDS · Doctor of Dental Surgery: A licensed dentist; DDS and DMD are equivalent dental degrees. About the DDS credential

Other identifiers

Identifier Type State Issuer
33725800 Medicaid WI -

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 1013931823 active?
Yes, as of the latest NPPES snapshot, NPI 1013931823 is active (record last updated 2007-07-08).
How do I verify William Brennan's NPI record?
Cross-check NPI 1013931823 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.