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Dr. William Ritchie Mackenzie, M.D.

Infectious Disease Physician in Mather, CA · enumerated 2006.

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

National Provider Identifier

1073561601

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Registry record

Entity type Individual (Type 1)
Name Dr. William Ritchie Mackenzie
Credential M.D.
Sex Male
Practice address 10535 Hospital Way, Mather, CA, 95655
Phone (916) 843-7107
Enumeration date May 5, 2006
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

207RI0200X Infectious Disease Physician Allopathic & Osteopathic Physicians · License G59633 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD 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 1073561601 active?
Yes, as of the latest NPPES snapshot, NPI 1073561601 is active (record last updated 2007-07-08).
How do I verify William Mackenzie's NPI record?
Cross-check NPI 1073561601 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.