DR. MARK CLAY WILLIAMS (PHD) – Clinical Psychologist, NPI 1619998416

DR. MARK CLAY WILLIAMS (PHD) is a healthcare provider. based in Altamonte springs, Florida. specializing in Clinical Psychologist. They hold the professional credentials PHD. They hold a License No. PY0003957 (FL). The NPI Number for DR. MARK CLAY WILLIAMS (PHD) is 1619998416

Main info

Male
Name
DR. MARK CLAY WILLIAMS (PHD)
NPI
1619998416
Phone
(407) 831-3446
Address
989 ORIENTA AVE
Enumeration Date
21 July 2006
Last Update Date
8 July 2007
Data current as of
19 May 2026

Profile Insights

NPPES metrics only — not quality of care.

Methodology
Experience52
Completeness75
Years active:19State licenses:1Digital endpointsOther names

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Provider Addresses for DR. MARK CLAY WILLIAMS (PHD)

  • 989, Orienta Avenue, Altamonte Springs, Seminole County, Florida, 32701, United States

    LIFE CARE CENTER OF ALTAMONTE

    ALTAMONTE SPRINGS, FL 32701

    Phone: (407) 831-3446

    Type: Location

  • 3851, Ethan Lane, Baldwin Park, Orlando, Orange County, Florida, 32814, United States

    ORLANDO, FL 328146567

    Phone: (407) 647-8437

    Fax: (407) 647-8437

    Type: Mailing

NPPES updates history

No NPPES updates recorded for this provider.

Prescription Activity

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Open Payments (CMS)

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Medicare Enrollment & Revalidation

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Educational use only—not medical, billing, or legal advice.

No Medicare enrollment or revalidation data available for this provider in our database.

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Medicare Utilization (FFS)

Source: CMS public data · Not endorsed by CMS · Beneficiary counts under 11 are suppressed in source data ·

Educational use only—not medical, billing, or legal advice.

Top Medicare procedures (2023) · refreshed 2026-05-27

HCPCSDescriptionServicesBeneficiariesMedicare allowed
90791Psychiatric diagnostic evaluation7979$0
90832Psychotherapy, 30 minutes4738$0
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Insurance plans in this area (ZIP 32701)

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Reviews

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Frequently asked questions

What is the 10-digit NPI for DR. MARK CLAY WILLIAMS (PHD)?
DR. MARK CLAY WILLIAMS (PHD) — NPI 1619998416 — is the standard way to identify this listing.
Can I rely on DR. MARK CLAY WILLIAMS (PHD) being an active provider?
As of the registry snapshot, DR. MARK CLAY WILLIAMS (PHD) is marked active.
What is DR. MARK CLAY WILLIAMS (PHD)'s specialty?
The listing groups DR. MARK CLAY WILLIAMS (PHD) with Clinical Psychologist. Clinical services aligned with this taxonomy classification.
Where should I expect DR. MARK CLAY WILLIAMS (PHD) on a map?
Expect Altamonte Springs, Florida as a primary anchor for DR. MARK CLAY WILLIAMS (PHD) unless the record lists multiple sites.
Why does DR. MARK CLAY WILLIAMS (PHD) have multiple addresses?
2 practice locations appear in the available data. Multiple addresses are common for hospital privileges, telehealth, or multi-site groups.

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