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Ontario Street Operatory

Ambulatory Surgical Clinic/Center in Chicago, IL · enumerated 2019 · authorized official Jeffrey Weinzweig, Owner.

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

National Provider Identifier

1477017333

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Registry record

Entity type Organization (Type 2)
Legal business name Ontario Street Operatory
Practice address 22 W Ontario St, Chicago, IL, 60654
Phone (312) 642-0400
Enumeration date Jan 24, 2019
Last updated in NPPES Feb 5, 2019

Taxonomy & classification

261QA1903X Ambulatory Surgical Clinic/Center Ambulatory Health Care Facilities Primary

Authorized official

Name Jeffrey Weinzweig
Title Owner
Phone (312) 642-0400

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 Ontario Street Operatory?
NPPES lists Jeffrey Weinzweig (Owner) as the authorized official for this organization.
What is the NPI number for Ontario Street Operatory?
The NPI for Ontario Street Operatory is 1477017333, 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 2019-02-05.