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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Mark L Horowitz, M.D.

Pediatrics Physician in Warwick, NY · enumerated 2006.

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

National Provider Identifier

1477649853

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Registry record

Entity type Individual (Type 1)
Name Mark L Horowitz
Credential M.D.
Sex Male
Practice address 10 Ronald Reagan Blvd, Warwick, NY, 10990
Phone (845) 986-2058
Fax (845) 986-7669
Enumeration date Oct 5, 2006
Last updated in NPPES Jun 17, 2009

Taxonomy & licenses

208000000X Pediatrics Physician Allopathic & Osteopathic Physicians · License 135749-1 (NY) Primary
208000000X Pediatrics Physician Allopathic & Osteopathic Physicians · License 25MA06649400 (NJ) Secondary
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
00513617 Medicaid NY -
0283908 Medicaid NJ -

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 NPI 1477649853 active?
Yes, as of the latest NPPES snapshot, NPI 1477649853 is active (record last updated 2009-06-17).
How do I verify Mark Horowitz's NPI record?
Cross-check NPI 1477649853 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2009-06-17.