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

Mr. John Joseph Duff, LMSW

Individual provider Social Worker · NPI 1568904589

Mr. John Joseph Duff, LMSW is a Social Worker in Jefferson Valley, New York. Licensed in New York. Registered with an NPI since 2016.

Licensed in
NY
In the registry since
2016
What do these letters mean?
LMSW — Licensed Master Social Worker
A master's-level social worker, usually practising under supervision.

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Practice location Address checks out

3630 Hill Blvd
Jefferson Valley, NY 10535
Phone: (914) 643-3810
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Social Worker (primary) Taxonomy 104100000X · Licence 051084-1 (NY)

Record details

NPI number1568904589
Entity typeIndividual (Type 1)
GenderMale
Credentials LMSW
Sole proprietorNo
NPI enumeratedNovember 8, 2016
Last updated in NPPESNovember 8, 2016

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