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

Joan H. Mass, MD

Individual provider Internal Medicine Physician · NPI 1295708162

Joan H. Mass, MD is an Internal Medicine Physician in Saint Charles, Missouri. Licensed in Missouri. Registered with an NPI since 2006.

Licensed in
MO
In the registry since
2006
Specialties on file
2
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

300 1st Capitol Dr
Saint Charles, MO 63301-2844
Phone: (636) 947-5000
Fax: (314) 317-0606
Show map & directions

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

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence R9A66 (MO)
Hospitalist Physician Taxonomy 208M00000X · Licence R9A66 (MO)

Record details

NPI number1295708162
Entity typeIndividual (Type 1)
GenderFemale
Credentials MD
Sole proprietorNo
NPI enumeratedFebruary 9, 2006
Last updated in NPPESMay 4, 2012
Mailing address12125 Woodcrest Executive Dr, Suite 220, Saint Louis, MO 63141-5001

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