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

Dr. Gregory Adam Witkin, PHD

Individual provider Psychologist · NPI 1245606920

Dr. Gregory Adam Witkin, PHD is a Psychologist in Wilmington, Delaware. Licensed in Delaware, New Jersey and New York. Registered with an NPI since 2015.

Licensed in
DE, NJ, NY
In the registry since
2015
Specialties on file
3
What do these letters mean?
PHD — Doctor of Philosophy
A research doctorate. In healthcare it usually sits alongside a clinical licence.

See every abbreviation used in this directory →

Practice location Address checks out

1600 Rockland Rd
Wilmington, DE 19803-3607
Phone: (302) 651-4200
Fax: (646) 754-9538
Show map & directions

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

Specialties & licences

Clinical Neuropsychologist (primary) Taxonomy 103G00000X · Licence B1-0001105 (DE)
Psychologist Taxonomy 103T00000X · Licence 021232 (NY)
Clinical Child & Adolescent Psychologist Taxonomy 103TC2200X · Licence 35S100566000 (NJ)

Record details

NPI number1245606920
Entity typeIndividual (Type 1)
GenderMale
Credentials PHD
Sole proprietorNo
NPI enumeratedAugust 17, 2015
Last updated in NPPESNovember 29, 2017
Mailing addressPo Box 191, Rockland, DE 19732-0191

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