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Ari Chaim Greis, DO

Physical Medicine & Rehabilitation Physician in Bryn Mawr, PA · enumerated 2006.

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

National Provider Identifier

1831209105

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Registry record

Entity type Individual (Type 1)
Name Ari Chaim Greis
Credential DO
Sex Male
Practice address 825 Old Lancaster Rd Ste 100, Bryn Mawr, PA, 19010
Phone (267) 339-3558
Fax (267) 339-3763
Enumeration date Aug 30, 2006
Last updated in NPPES May 9, 2024

Taxonomy & licenses

208100000X Physical Medicine & Rehabilitation Physician Allopathic & Osteopathic Physicians · License 25MB09081300 (NJ) Secondary
208100000X Physical Medicine & Rehabilitation Physician Allopathic & Osteopathic Physicians · License OS014246 (PA) Primary
DO · Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO credential

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

Where does Ari Greis practice?
The practice location on file with NPPES is in Bryn Mawr, PA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Ari Greis?
The National Provider Identifier (NPI) for Ari Greis is 1831209105, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2024-05-09.