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Mark R Thorson, MD

Internal Medicine Physician in Longview, WA · enumerated 2005.

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

National Provider Identifier

1609877141

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Registry record

Entity type Individual (Type 1)
Name Mark R Thorson
Credential MD
Sex Male
Practice address 1615 Delaware St, Longview, WA, 98632
Phone (360) 501-3601
Fax (360) 501-3648
Enumeration date Aug 9, 2005
Last updated in NPPES Jul 30, 2012

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License MD00015441 (WA) 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
8239097 Medicaid WA -
110194826 Other - RR MEDICARE
126456 Other WA LABOR & IND.
058339 Medicaid OR -
8923178 Other WA CRIME VICTIMS

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 Mark Thorson practice?
The practice location on file with NPPES is in Longview, WA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mark Thorson?
The National Provider Identifier (NPI) for Mark Thorson is 1609877141, 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 2012-07-30.