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Allergy, Asthma & Sinus Center, S.C.

Specialist in Greenfield, WI · enumerated 2006 · authorized official Gary Steven, Owner.

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

National Provider Identifier

1265546303

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Registry record

Entity type Organization (Type 2)
Legal business name Allergy, Asthma & Sinus Center, S.C.
Practice address 8585 W Forest Home Ave, Suite 200, Greenfield, WI, 53228
Phone (414) 529-8500
Fax (414) 529-8511
Enumeration date Aug 18, 2006
Last updated in NPPES Sep 17, 2009

Taxonomy & classification

174400000X Specialist Other Service Providers · License 33574020 (WI) Primary

Authorized official

Name Gary Steven
Title Owner
Phone (414) 529-8500

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 Allergy, Asthma & Sinus Center, S.C.?
NPPES lists Gary Steven (Owner) as the authorized official for this organization.
What is the NPI number for Allergy, Asthma & Sinus Center, S.C.?
The NPI for Allergy, Asthma & Sinus Center, S.C. is 1265546303, 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 2009-09-17.