Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

O'Neil R Mason, MD

Individual provider Internal Medicine Physician · NPI 1699046748

O'Neil R Mason, MD is a Cardiovascular Disease (Cardiology) in Morristown, New Jersey. Qualified in 2005, 21 years ago. Practices with Practice Associates Medical Group, a 1,403-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in Illinois, New Jersey and New York.

Years since qualifying
21
Licensed in
IL, NJ, NY
In the registry since
2012
Specialties on file
3
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

100 Madison Ave
Morristown, NJ 07960-6136
Phone: (973) 971-7416
Fax: (973) 401-2470
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 676 N Saint Clair St, Chicago, IL 60611-2927 — (312) 926-2000

Specialties & licences

Cardiovascular Disease Physician (primary) Taxonomy 207RC0000X · Licence 25MA11494000 (NJ)
Internal Medicine Physician Taxonomy 207R00000X · Licence 266546 (NY)
Cardiovascular Disease Physician Taxonomy 207RC0000X · Licence 036152383 (IL)

Record details

NPI number1699046748
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorYes
NPI enumeratedJanuary 21, 2012
Last updated in NPPESSeptember 1, 2022
Certification dateSeptember 1, 2022

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyCARDIOVASCULAR DISEASE (CARDIOLOGY)
Also practisesINTERNAL MEDICINE
Medical schoolOTHER
Graduated 2005 (21 years in practice)
Group practice Practice Associates Medical Group — 1403 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations2 on file with Medicare

Other providers in Morristown