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Mark A Tidswell, MD

Critical Care Medicine (Internal Medicine) Physician in Springfield, MA · enumerated 2006.

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

National Provider Identifier

1699722066

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Registry record

Entity type Individual (Type 1)
Name Mark A Tidswell
Credential MD
Sex Male
Practice address 759 Chestnut Street, S2668, Springfield, MA, 01199
Phone (413) 794-5439
Fax (413) 794-5389
Enumeration date May 30, 2006
Last updated in NPPES Apr 1, 2011

Taxonomy & licenses

207RP1001X Pulmonary Disease Physician Allopathic & Osteopathic Physicians · License 161219 (MA) Secondary
207RC0200X Critical Care Medicine (Internal Medicine) Physician Allopathic & Osteopathic Physicians · License 161219 (MA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD 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.

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Frequently asked questions

What is the NPI number for Mark Tidswell?
The National Provider Identifier (NPI) for Mark Tidswell is 1699722066, a Type 1 (individual) record in the CMS NPPES registry.
Where does Mark Tidswell practice?
The practice location on file with NPPES is in Springfield, MA. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-04-01.