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David M Mattson Jr., MD

Radiation Oncology Physician in Buffalo, NY · enumerated 2007.

Data current as of Jul 11, 2026 · sourced from CMS NPPES

National Provider Identifier

1134336621

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Registry record

Entity type Individual (Type 1)
Name David M Mattson Jr.
Credential MD
Sex Male
Practice address Elm and Carlton St, Buffalo, NY, 14263
Phone (716) 845-2300
Fax (716) 845-7616
Enumeration date May 16, 2007
Last updated in NPPES Feb 15, 2021

Taxonomy & licenses

2085R0001X Radiation Oncology Physician Allopathic & Osteopathic Physicians · License 251127 (NY) 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
03048831 Medicaid NY —

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 David Mattson practice?
The practice location on file with NPPES is in Buffalo, NY. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for David Mattson?
The National Provider Identifier (NPI) for David Mattson is 1134336621, 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 2026-07-11. Provider record last updated 2021-02-15.