DR. WILLIAM HARRISON MELLICK III PHD
NPI 1154040293
Psychologist - Clinical in Charleston, SC

Active since August 23, 2022PECOS EnrolledAccepts Medicare Assignment
171 ASHLEY AVE, CHARLESTON, SC 29425(843) 792-1414 Get Directions Write a Review

NPPES record last updated: September 9, 2025. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Sep 9, 2025, Aug 23, 2022 (2 updates tracked since 2022).

About Dr. William Harrison Mellick Iii Phd NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. WILLIAM HARRISON MELLICK III PHD (NPI 1154040293) is an individual clinical provider in Charleston, South Carolina, licensed in South Carolina (1542) and active in the NPI registry since August 2022. He is enrolled in Medicare PECOS and is a graduate of Other (2017).

NPPES Registry Identity

NPI1154040293
Entity TypeIndividualMale
Primary Taxonomy103TC0700X
Provider Legal NameDR. WILLIAM HARRISON MELLICK IIICredential: PHD
Location Address171 ASHLEY AVECharleston, SC 29425-8908
Mailing AddressPo Box 751461Charlotte, NC 28275-1461
Sole ProprietorNo
Medical School CMSOtherGraduated 2017
Enumeration DateAugust 23, 2022
Last NPPES UpdateSeptember 9, 20252 updates tracked since enumeration
NPPES CertifiedSeptember 9, 2025
NPI 1154040293 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 5

Primary SpecialtyPsychologist · ClinicalBehavioral Health & Social Service Providers
Taxonomy Code103TC0700X
License Licensed in SC · 1542
Definition
A psychologist who provides continuing and comprehensive mental and behavioral health care for individuals and families; consultation to agencies and communities; training, education and supervision; and research-based practice. It is a specialty in breadth -- one that is broadly inclusive of severe psychopathology -- and marked by comprehensiveness and integration of knowledge and skill from a broad array of disciplines within and outside of psychology proper. The scope of clinical psychology encompasses all ages, multiple diversities and varied systems.
Also ListedPsychologist · Addiction (Substance Use Disorder)Taxonomy 103TA0400X · License 1542 (SC)
Also ListedPsychologist · Cognitive & BehavioralTaxonomy 103TB0200X · License 1542 (SC)
Also ListedPsychologist · Clinical Child & AdolescentTaxonomy 103TC2200X · License 1542 (SC)
Also ListedPsychologist · FamilyTaxonomy 103TF0000X · License 1542 (SC)
171 ASHLEY AVE, Charleston, SC 29425

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

Enrolled in Medicare and accepts Medicare assignment

Dr. William Harrison Mellick Iii Phd is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID7315443835
PECOS Enrollment IDI20251003000475
Eligible to Order & Refer Part B Labs & Imaging Durable Medical Equipment Home Health Agency Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 29425 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$163.84 typical visit price
range $53.57 – $163.84
Typical copayment $40.96 (range $13.39 – $40.96)
Most-billed visit code 99205
Established Patient
$95.12 typical visit price
range $16.96 – $133.52
Typical copayment $23.78 (range $4.24 – $33.38)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

Allergy & Immunology
171 ASHLEY AVE
CHARLESTON, SC 29425
Nurse Anesthetist, Certified Registered
171 ASHLEY AVE
CHARLESTON, SC 29425
Pathology (Anatomic Pathology)
171 ASHLEY AVE
CHARLESTON, SC 29425
Ophthalmology
171 ASHLEY AVE
CHARLESTON, SC 29425
Social Worker
171 ASHLEY AVE
CHARLESTON, SC 29425
Radiology (Pediatric Radiology)
171 ASHLEY AVE
CHARLESTON, SC 29425
Nurse Practitioner
171 ASHLEY AVE
CHARLESTON, SC 29425
Ophthalmology
171 ASHLEY AVE
CHARLESTON, SC 29425

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is William Mellick's NPI number?

The NPI number for William Mellick is 1154040293. It was assigned to this individual provider in the NPPES registry on August 23, 2022.

Where is William Mellick located?

William Mellick practices at 171 Ashley Ave, Charleston, SC 29425. The listed phone number is (843) 792-1414.

What is William Mellick's specialty?

The primary specialty registered for this NPI is Psychologist, specializing in Clinical, with taxonomy code 103TC0700X.

Is William Mellick enrolled in Medicare?

Yes. William Mellick is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

When was this NPI record last updated?

The NPPES record for William Mellick was last updated on September 9, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.