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Dr. William Macgregor Green, MD

Emergency Medicine Physician in South Lake Tahoe, CA · enumerated 2005.

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

National Provider Identifier

1871591099

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Registry record

Entity type Individual (Type 1)
Name Dr. William Macgregor Green
Credential MD
Sex Male
Practice address 2170 South Ave, South Lake Tahoe, CA, 96150
Fax (530) 543-8683
Enumeration date Jul 12, 2005
Last updated in NPPES Sep 20, 2012

Taxonomy & licenses

207P00000X Emergency Medicine Physician Allopathic & Osteopathic Physicians · License G27289 (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
1871591099 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.

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Frequently asked questions

Where does William Green practice?
The practice location on file with NPPES is in South Lake Tahoe, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for William Green?
The National Provider Identifier (NPI) for William Green is 1871591099, a Type 1 (individual) record in the CMS NPPES registry.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-09-20.