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Dr. Samuel Stack, OD

Optometrist in Littleton, NH · enumerated 2020.

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

National Provider Identifier

1114542149

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Registry record

Entity type Individual (Type 1)
Name Dr. Samuel Stack
Credential OD
Sex Male
Practice address 104 Meadow St, Littleton, NH, 03561
Phone (603) 444-2592
Enumeration date Jun 16, 2020
Last updated in NPPES Aug 27, 2021

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License OEG003662 (PA) Secondary
152W00000X Optometrist Eye and Vision Services Providers · License 1042 (NH) Primary
OD · Doctor of Optometry: A licensed optometrist providing primary vision care, eye exams, and corrective lenses. About the OD 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 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 Samuel Stack?
Samuel Stack is registered in NPPES with the primary taxonomy of Optometrist. 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 2021-08-27.