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

Dr. William Harrison Mellick III, PHD

Individual provider Addiction (Substance Use Disorder) Psychologist · NPI 1154040293

Dr. William Harrison Mellick III, PHD is a Clinical Psychologist in Charleston, South Carolina. Qualified in 2017, 9 years ago. Practices with University Medical Associates of the Medical University of South Carol, a 1,640-clinician group and accepts Medicare assignment. Licensed in South Carolina.

Years since qualifying
9
Licensed in
SC
In the registry since
2022
Specialties on file
5
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

171 Ashley Ave
Charleston, SC 29425-8908
Phone: (843) 792-1414
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Clinical Psychologist (primary) Taxonomy 103TC0700X · Licence 1542 (SC)
Addiction (Substance Use Disorder) Psychologist Taxonomy 103TA0400X · Licence 1542 (SC)
Family Psychologist Taxonomy 103TF0000X · Licence 1542 (SC)
Cognitive & Behavioral Psychologist Taxonomy 103TB0200X · Licence 1542 (SC)
Clinical Child & Adolescent Psychologist Taxonomy 103TC2200X · Licence 1542 (SC)

Record details

NPI number1154040293
Entity typeIndividual (Type 1)
GenderMale
Credentials PHD
Sole proprietorNo
NPI enumeratedAugust 23, 2022
Last updated in NPPESSeptember 9, 2025
Certification dateSeptember 9, 2025

Medicare enrollment

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

Medicare specialtyCLINICAL PSYCHOLOGIST
Medical schoolOTHER
Graduated 2017 (9 years in practice)
Group practice University Medical Associates Of The Medical University Of South Carol — 1640 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

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