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Dr. William Matthew Mahon, M.D.

Pediatric Adolescent Medicine Physician in Fort Bragg, CA · enumerated 2006.

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

National Provider Identifier

1184646259

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Registry record

Entity type Individual (Type 1)
Name Dr. William Matthew Mahon
Credential M.D.
Sex Male
Practice address 510 Cypress St Ste D, Fort Bragg, CA, 95437
Phone (707) 964-5696
Fax (707) 964-6274
Enumeration date Jul 24, 2006
Last updated in NPPES Feb 15, 2012

Taxonomy & licenses

2080A0000X Pediatric Adolescent Medicine Physician Allopathic & Osteopathic Physicians · License G30967 (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
OOG309670 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.

Read the full guide → Validate an NPI →

Frequently asked questions

Is NPI 1184646259 active?
Yes, as of the latest NPPES snapshot, NPI 1184646259 is active (record last updated 2012-02-15).
How do I verify William Mahon's NPI record?
Cross-check NPI 1184646259 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 2012-02-15.