NPI Portal NPI Lookup & Verification

John J Warner, MD

John J Warner is a Diagnostic Radiology Physician provider (Radiology) practicing in Marshfield, WI, registered in the NPPES registry with NPI 1831291871 since 2006. The credential MD stands for Doctor of Medicine.

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NPI 1831291871
Entity type Individual (Type 1)
Name John J Warner
Credential MD
Sex Male
Practice address 1000 N OAK AVE, Marshfield, WI, 54449
Phone 7153893555
Enumeration date 2006-09-01
Last updated in NPPES 2024-09-10

Taxonomy & licenses

Taxonomy code Specialty Primary License State
2085R0202X Diagnostic Radiology Physician Primary 28299 WI

MD — Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
30815000 Medicaid WI
Copy-ready billing details
Provider: John Warner, MD
NPI: 1831291871
Taxonomy: 2085R0202X (Diagnostic Radiology Physician)
Address: 1000 N OAK AVE, Marshfield, WI, 54449

Other providers at this practice address

NPI Name Type Specialty Location
1518963347 Ivan Maldonado Individual Trauma Surgery Physician Marshfield, WI
1932106689 Milan Pastuovic Individual Oral and Maxillofacial Surgery (Dentist) Marshfield, WI
1073510731 John Cordova Individual Critical Care Medicine (Internal Medicine) Physician Marshfield, WI
1295732923 Michael Rudolph Individual Anesthesiology Physician Marshfield, WI
1326032509 Jason Duelge Individual Radiation Oncology Physician Marshfield, WI
1871587584 Brett Carmichael Individual Diagnostic Radiology Physician Marshfield, WI
1447245816 Corey Massey Individual Emergency Medicine Physician Marshfield, WI
1861480055 Frederick Gehrmann Individual Anesthesiology Physician Marshfield, WI

Verify this record

Cross-check NPI 1831291871 against the authoritative CMS record: view John J Warner on the official NPPES registry .

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. Read the full guide or validate an NPI number.

Frequently asked questions

Is NPI 1831291871 active?
Yes — as of the latest NPPES snapshot, NPI 1831291871 is active (record last updated 2024-09-10).
How do I verify John Warner's NPI record?
Cross-check NPI 1831291871 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2024-09-10.