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

William O Thomason, PHD

Individual provider Addiction (Substance Use Disorder) Psychologist · NPI 1912069543

William O Thomason, PHD is an Addiction (Substance Use Disorder) Psychologist in Terrell, Texas. Licensed in Texas. Registered with an NPI since 2006.

Licensed in
TX
In the registry since
2006
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

1200 E Brin St
Terrell, TX 75160
Phone: (972) 551-8826
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Family Psychologist (primary) Taxonomy 103TF0000X · Licence 25481 (TX)
Addiction (Substance Use Disorder) Psychologist Taxonomy 103TA0400X · Licence 25481 (TX)
Clinical Psychologist Taxonomy 103TC0700X · Licence 25481 (TX)

Record details

NPI number1912069543
Entity typeIndividual (Type 1)
GenderMale
Credentials PHD
Sole proprietorNo
NPI enumeratedDecember 13, 2006
Last updated in NPPESSeptember 11, 2025
Mailing addressPo Box 70, Terrell, TX 75160

Other providers in Terrell