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John Walker, ASAC

Addiction (Substance Use Disorder) Counselor in Commack, NY · enumerated 2007.

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

National Provider Identifier

1114047545

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Registry record

Entity type Individual (Type 1)
Name John Walker
Credential ASAC
Sex Male
Practice address 155 Indian Head Rd, Commack, NY, 11725
Phone (631) 543-6200
Enumeration date Mar 30, 2007
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

101YA0400X Addiction (Substance Use Disorder) Counselor Behavioral Health & Social Service Providers · License 12833 (NY) Primary

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 this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is John Walker?
John Walker is registered in NPPES with the primary taxonomy of Addiction (Substance Use Disorder) Counselor. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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