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

Matthew J Siekkinen, LCSW

Individual provider Clinical Social Worker · NPI 1003308768

Matthew J Siekkinen, LCSW is a Clinical Social Worker in Greencastle, Indiana. Qualified in 2013, 13 years ago. Practices with Hamilton Center, Inc, a 43-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in Indiana.

Years since qualifying
13
Licensed in
IN
In the registry since
2018
Specialties on file
2
What do these letters mean?
LCSW — Licensed Clinical Social Worker
A social worker licensed to diagnose and treat mental health conditions independently.

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Practice location Address checks out

239 Hillsdale Ave
Greencastle, IN 46135-1340
Phone: (765) 653-1024
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 2401 W University Ave Fl 3, Muncie, IN 47303-3428 — (765) 751-1701

Specialties & licences

Clinical Social Worker (primary) Taxonomy 1041C0700X · Licence 34012446A (IN)
Social Worker Taxonomy 104100000X · Licence 33007302A (IN)

Record details

NPI number1003308768
Entity typeIndividual (Type 1)
GenderMale
Credentials LCSW
Sole proprietorNo
NPI enumeratedMay 30, 2018
Last updated in NPPESDecember 8, 2025
Certification dateDecember 8, 2025

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyCLINICAL SOCIAL WORKER
Medical schoolOTHER
Graduated 2013 (13 years in practice)
Group practice Hamilton Center, Inc. — 43 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

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