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

MS. Sonia Malka Chessin, LAC, LCSW

Individual provider Addiction (Substance Use Disorder) Counselor · NPI 1306199336

MS. Sonia Malka Chessin, LAC, LCSW is a Clinical Social Worker in Missoula, Montana. Qualified in 1991, 35 years ago. Practices as a sole proprietor and accepts Medicare assignment. Licensed in Montana.

Years since qualifying
35
Licensed in
MT
In the registry since
2012
Specialties on file
2
What do these letters mean?
LAC — Licensed Associate Counselor
A counsellor practising under supervision toward full licensure. In some states the same letters mean Licensed Acupuncturist.
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

301 W Sussex Ave
Missoula, MT 59801-6840
Phone: (406) 370-5308
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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 · Licence 1047 (MT)
Addiction (Substance Use Disorder) Counselor Taxonomy 101YA0400X · Licence 1245 (MT)

Record details

NPI number1306199336
Entity typeIndividual (Type 1)
GenderFemale
Credentials LAC , LCSW
Sole proprietorYes
NPI enumeratedOctober 15, 2012
Last updated in NPPESOctober 15, 2012

Medicare enrollment

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

Medicare specialtyCLINICAL SOCIAL WORKER
Medical schoolOTHER
Graduated 1991 (35 years in practice)
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations2 on file with Medicare

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