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

Justin Sean Gillis LLC

Organization Clinical Social Worker · NPI 1023642253

Justin Sean Gillis LLC is a Clinical Social Worker in Belmont, Massachusetts. Registered with an NPI since 2020.

In the registry since
2020
What do these letters mean?
LLC — Limited liability company
A form of business registration, not a clinical qualification.

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Practice location Address checks out

115 Mill St
Belmont, MA 02478-1064
Phone: (617) 855-2459
Fax: (617) 855-3470
Show map & directions

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

Specialties & licences

Clinical Social Worker (primary) Taxonomy 1041C0700X

Record details

NPI number1023642253
Entity typeOrganization (Type 2)
Organization subpartNo
Authorized official Justin Gillis — Owner · (774) 273-0594
NPI enumeratedFebruary 26, 2020
Last updated in NPPESFebruary 26, 2020
Certification dateFebruary 26, 2020
Mailing address115 Mill St, Belmont, MA 02478-1064

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