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Katherine O'Sullivan, LCSW

Katherine O'Sullivan is a Clinical Social Worker provider (Social Worker) practicing in Brewster, NY, registered in the NPPES registry with NPI 1619731908 since 2024. The credential LCSW stands for Licensed Clinical Social Worker.

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NPI 1619731908
Entity type Individual (Type 1)
Name Katherine O'Sullivan
Credential LCSW
Sex Female
Practice address 21 MARLIN RD, Brewster, NY, 10509
Phone 6467347891
Enumeration date 2024-02-07
Last updated in NPPES 2024-02-07

Taxonomy & licenses

Taxonomy code Specialty Primary License State
1041C0700X Clinical Social Worker Primary 081032-1 NY

LCSW — Licensed Clinical Social Worker: A social worker licensed for clinical practice including mental-health therapy. About the LCSW credential

Copy-ready billing details
Provider: Katherine O'Sullivan, LCSW
NPI: 1619731908
Taxonomy: 1041C0700X (Clinical Social Worker)
Address: 21 MARLIN RD, Brewster, NY, 10509

Verify this record

Cross-check NPI 1619731908 against the authoritative CMS record: view Katherine O'Sullivan on the official NPPES registry .

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. Read the full guide or validate an NPI number.

Frequently asked questions

What specialty is Katherine O'Sullivan?
Katherine O'Sullivan is registered in NPPES with the primary taxonomy of Clinical Social Worker. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
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.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2024-02-07.