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

William Guyler Niver, CSW

Individual provider Addiction (Substance Use Disorder) Counselor · NPI 1821318254

William Guyler Niver, CSW is an Addiction (Substance Use Disorder) Counselor in Cortland, New York. Practices as a sole proprietor. Licensed in New York.

Licensed in
NY
In the registry since
2010

Practice location Address checks out

17 Main St
Cortland, NY 13045-6606
Phone: (607) 756-4167
Fax: (607) 753-0608
Show map & directions

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

Specialties & licences

Addiction (Substance Use Disorder) Counselor (primary) Taxonomy 101YA0400X · Licence 8695 (NY)

Record details

NPI number1821318254
Entity typeIndividual (Type 1)
GenderMale
Credentials CSW
Sole proprietorYes
NPI enumeratedJune 8, 2010
Last updated in NPPESJune 8, 2010

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