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Greenwich Radiation Oncology

Radiation Oncology Physician in Rye, NY · enumerated 2007 · authorized official Daniel Fass, Director of Radiation Oncologist.

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

National Provider Identifier

1013131903

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Registry record

Entity type Organization (Type 2)
Legal business name Greenwich Radiation Oncology
Practice address 1 Theall Road, Ste 107, Rye, NY, 10580
Phone (914) 848-8950
Fax (914) 848-8951
Enumeration date Apr 12, 2007
Last updated in NPPES Mar 26, 2009

Taxonomy & classification

2085R0001X Radiation Oncology Physician Allopathic & Osteopathic Physicians · License 032191 (CT) Primary

Authorized official

Name Daniel Fass
Title Director of Radiation Oncologist
Phone (914) 848-8950

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

Who is the authorized official for Greenwich Radiation Oncology?
NPPES lists Daniel Fass (Director of Radiation Oncologist) as the authorized official for this organization.
What is the NPI number for Greenwich Radiation Oncology?
The NPI for Greenwich Radiation Oncology is 1013131903, a Type 2 (organization) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2009-03-26.