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

Marissa Fielstein, LMSW

Individual provider Social Worker · NPI 1619383668

Marissa Fielstein, LMSW is a Social Worker in Northport, New York. Practices as a sole proprietor. Licensed in New York.

Licensed in
NY
In the registry since
2014
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

79 Middleville Rd
Northport, NY 11768-2200
Phone: (631) 261-4400
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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 092019 (NY)

Record details

NPI number1619383668
Entity typeIndividual (Type 1)
GenderFemale
Credentials LMSW
Sole proprietorYes
NPI enumeratedJuly 9, 2014
Last updated in NPPESJuly 9, 2014

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