Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Mr. Michael Holtt

Addiction (Substance Use Disorder) Registered Nurse in Harrison, NY · enumerated 2012.

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

National Provider Identifier

1811248131

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Registry record

Entity type Individual (Type 1)

Name Mr. Michael Holtt

Sex Female

Practice address Harrison, NY, 10528

Phone (914) 925-5211

Enumeration date Sep 26, 2012

Last updated in NPPES Sep 26, 2012

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

163WA0400X Addiction (Substance Use Disorder) Registered Nurse Nursing Service Providers · License 625341 (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 Michael Holtt?

Michael Holtt is registered in NPPES with the primary taxonomy of Addiction (Substance Use Disorder) Registered Nurse. 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 2012-09-26.