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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Jillian M Viessman

Social Worker in Watertown, SD · enumerated 2015.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1366836264

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Registry record

Entity type Individual (Type 1)
Name Jillian M Viessman
Sex Female
Practice address Watertown, SD, 57201
Phone (605) 882-2740
Enumeration date Mar 28, 2015
Last updated in NPPES Mar 28, 2015

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

104100000X Social Worker Behavioral Health & Social Service Providers · License LCSW2958 (SD) Primary

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

What is the NPI number for Jillian Viessman?
The National Provider Identifier (NPI) for Jillian Viessman is 1366836264, a Type 1 (individual) record in the CMS NPPES registry.
Where does Jillian Viessman practice?
The practice location on file with NPPES is in Watertown, SD. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2015-03-28.