Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Gregory T Olson, D.O.

Family Medicine Physician in Sioux City, IA · enumerated 2010.

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

National Provider Identifier

1174841795

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Registry record

Entity type Individual (Type 1)

Name Gregory T Olson

Credential D.O.

Sex Male

Practice address 4545 Sergeant Rd, Sioux City, IA, 51106

Phone (712) 274-2400

Fax (712) 274-1487

Enumeration date May 6, 2010

Last updated in NPPES Nov 21, 2014

Taxonomy & licenses

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License 4203 (IA) Primary

DO · Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO 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.

Read the full guide → Validate an NPI →

Frequently asked questions

Where does Gregory Olson practice?

The practice location on file with NPPES is in Sioux City, IA. Providers can have multiple locations; NPPES lists the primary practice address.

What is the NPI number for Gregory Olson?

The National Provider Identifier (NPI) for Gregory Olson is 1174841795, a Type 1 (individual) record in the CMS NPPES registry.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2014-11-21.