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

Fiona Marie O'Sullivan, MSW

Individual provider Clinical Social Worker · NPI 1356127120

Fiona Marie O'Sullivan, MSW is a Clinical Social Worker in Pittsfield, Massachusetts. Registered with an NPI since 2023.

In the registry since
2023
What do these letters mean?
MSW — Master of Social Work
The graduate degree in social work.

See every abbreviation used in this directory →

Practice location Address checks out

359 Fenn St
Pittsfield, MA 01201-5261
Phone: (413) 499-0412
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Clinical Social Worker (primary) Taxonomy 1041C0700X

Record details

NPI number1356127120
Entity typeIndividual (Type 1)
GenderFemale
Credentials MSW
Sole proprietorNo
NPI enumeratedSeptember 6, 2023
Last updated in NPPESSeptember 6, 2023
Certification dateSeptember 6, 2023

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