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John W Sage, MD

Family Medicine Physician in Mount Prospect, IL · enumerated 2005.

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

National Provider Identifier

1972585636

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Registry record

Entity type Individual (Type 1)
Name John W Sage
Credential MD
Sex Male
Practice address 431 Lakeview Ct, Suite D, Mount Prospect, IL, 60056
Phone (847) 296-3040
Fax (847) 296-5546
Enumeration date Nov 17, 2005
Last updated in NPPES Feb 15, 2011

Taxonomy & licenses

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License 036051893 (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 John Sage?
The National Provider Identifier (NPI) for John Sage is 1972585636, a Type 1 (individual) record in the CMS NPPES registry.
Where does John Sage practice?
The practice location on file with NPPES is in Mount Prospect, 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 2011-02-15.