Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Seymour Alter, M.D.

Specialist in Smithtown, NY · enumerated 2006.

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

National Provider Identifier

1750336251

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Registry record

Entity type Individual (Type 1)

Name Dr. Seymour Alter

Credential M.D.

Sex Male

Practice address 222 Middle Country Rd, Suite 109, Smithtown, NY, 11787

Phone (631) 265-7711

Fax (631) 265-1225

Enumeration date May 23, 2006

Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

174400000X Specialist Other Service Providers · License 114051 (NY) 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
00425181	Medicaid	NY	-
114051	Other	NY	LICENSE

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 Seymour Alter?

Seymour Alter is registered in NPPES with the primary taxonomy of Specialist. 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.