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Grant Michael Wallenfelsz, MD

Emergency Medicine Physician in Agana Heights, GU · enumerated 2020 · practices at Nh Guam.

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

National Provider Identifier

1194353318

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Registry record

Entity type Individual (Type 1)
Name Grant Michael Wallenfelsz
Credential MD
Sex Male
Practice address Bldg #50 Farenholt Ave, Agana Heights, GU, 96910
Phone (671) 344-9340
Enumeration date Apr 1, 2020
Last updated in NPPES Oct 2, 2025

Taxonomy & licenses

207P00000X Emergency Medicine Physician Allopathic & Osteopathic Physicians · License T3715 (TX) Primary
207P00000X Emergency Medicine Physician Allopathic & Osteopathic Physicians · License A187218 (CA) Secondary
207P00000X Emergency Medicine Physician Allopathic & Osteopathic Physicians · License M-2480 (GU) Secondary
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 Grant Wallenfelsz?
The National Provider Identifier (NPI) for Grant Wallenfelsz is 1194353318, a Type 1 (individual) record in the CMS NPPES registry.
Where does Grant Wallenfelsz practice?
The practice location on file with NPPES is in Agana Heights, GU. 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 2025-10-02.