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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Ariel Reuven Katz, M.D.

Internal Medicine Physician in Chicago, IL · enumerated 2006 · practices at Advocate Health and Hospitals Corporation.

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

National Provider Identifier

1245261684

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Registry record

Entity type Individual (Type 1)
Name Dr. Ariel Reuven Katz
Credential M.D.
Sex Male
Practice address 3134 N Clark St, Chicago, IL, 60657
Phone (312) 296-5090
Enumeration date Jul 5, 2006
Last updated in NPPES Jan 29, 2025

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 036-114147 (IL) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD 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

What is the NPI number for Ariel Katz?
The National Provider Identifier (NPI) for Ariel Katz is 1245261684, a Type 1 (individual) record in the CMS NPPES registry.
Where does Ariel Katz practice?
The practice location on file with NPPES is in Chicago, IL. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-01-29.