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Gregory R. Larson, MD

Family Medicine Physician in Watertown, SD · enumerated 2006.

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

National Provider Identifier

1629036645

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Registry record

Entity type Individual (Type 1)
Name Gregory R. Larson
Credential MD
Sex Male
Practice address 511 14th Ave Ne, Watertown, SD, 57201
Phone (605) 886-8482
Fax (605) 884-4300
Enumeration date May 1, 2006
Last updated in NPPES May 17, 2022

Taxonomy & licenses

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License 3698 (SD) 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
5609624 Medicaid SD -

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

Where does Gregory Larson practice?
The practice location on file with NPPES is in Watertown, SD. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Gregory Larson?
The National Provider Identifier (NPI) for Gregory Larson is 1629036645, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2022-05-17.