Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Nathaniel James Stewart, M.D.

Orthopaedic Surgery Physician in Altoona, WI · enumerated 2006 · practices at Chippewa Valley Orthopedics and Sports Medicine Clinic Sc.

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

National Provider Identifier

1225064017

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Registry record

Entity type Individual (Type 1)

Name Nathaniel James Stewart

Credential M.D.

Sex Male

Practice address 1200 Oakleaf Way Ste A, Altoona, WI, 54720

Phone (715) 832-1400

Fax (715) 832-4187

Enumeration date Jun 23, 2006

Last updated in NPPES Jun 5, 2026

Taxonomy & licenses

207X00000X Orthopaedic Surgery Physician Allopathic & Osteopathic Physicians · License 39520 (WI) Primary

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
32400600	Medicaid	WI	-
85410	Other	WI	SECURITY HEALTH PLAN
378L4ST	Other	WI	BCBS MN
09 01123	Other	WI	MEDICA/SELECTCARE EC
1930920	Other	WI	UNITED HEALTHCARE
208036400	Other	WI	OWCP
P00136555	Other	WI	RAILROAD MEDICARE
09-01124	Other	WI	MEDICA/SELECTCARE CF
2110231	Other	WI	FIRST HEALTH

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

Is this the official NPI registry?

No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

What specialty is Nathaniel Stewart?

Nathaniel Stewart is registered in NPPES with the primary taxonomy of Orthopaedic Surgery Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2026-06-05.