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

Dr. Steven J Mason, MD

Individual provider Cardiovascular Disease Physician · NPI 1366445603

Dr. Steven J Mason, MD is registered under Cardiovascular Disease (Cardiology) in Baltimore, Maryland. Graduated from Harvard Medical School in 1972, 54 years ago. Practices with Johns Hopkins University, a 2,855-clinician group. Licensed in Maryland.

Years since qualifying
54
Trained at
Harvard Medical School
Licensed in
MD
In the registry since
2005
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Practice location Address checks out

9105 Franklin Square Dr Ste 209
Baltimore, MD 21237-3958 Not confirmed with CMS for 16 years — call before visiting
Phone: (410) 574-1330
Fax: (410) 574-2691
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Cardiovascular Disease Physician (primary) Taxonomy 207RC0000X · Licence D0017347 (MD)

Record details

NPI number1366445603
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedMay 31, 2005
Last updated in NPPESAugust 30, 2010

Medicare enrollment

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

Medicare specialtyCARDIOVASCULAR DISEASE (CARDIOLOGY)
Also practisesINTERNAL MEDICINE
Medical schoolHARVARD MEDICAL SCHOOL
Graduated 1972 (54 years in practice)
Group practice Johns Hopkins University — 2855 clinicians
Accepts Medicare assignment Not indicated
Practice locations6 on file with Medicare

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients620
Services billed 848 a service is one billed item, such as a visit, a test or a procedure
Average patient age79

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Johns Hopkins University

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 2855 clinicians in the practice; 12 are shown here.

Other providers in Baltimore