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Dr. Samuel Evan Day, MD, PHD

Radiation Oncology Physician in Tucson, AZ · enumerated 2014.

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

National Provider Identifier

1811304652

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Registry record

Entity type Individual (Type 1)
Name Dr. Samuel Evan Day
Credential MD, PHD
Sex Male
Practice address 3700 E Fort Lowell Rd Ste 130, Tucson, AZ, 85716
Phone (520) 881-0631
Fax (520) 526-1773
Enumeration date Jul 14, 2014
Last updated in NPPES Aug 11, 2022

Taxonomy & licenses

2085R0001X Radiation Oncology Physician Allopathic & Osteopathic Physicians · License 58485 (AZ) 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

How do I verify Samuel Day's NPI record?
Cross-check NPI 1811304652 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1811304652 active?
Yes, as of the latest NPPES snapshot, NPI 1811304652 is active (record last updated 2022-08-11).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2022-08-11.