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Dr. Michael Andrew Williston, PSY.D.

Psychologist in Wilmington, DE · enumerated 2011 · practices at Christianacare Virtual Health Practice PA.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1093090474

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Registry record

Entity type Individual (Type 1)
Name Dr. Michael Andrew Williston
Credential PSY.D.
Sex Male
Practice address 4000 Nexus Dr Ste Ne3-100, Wilmington, DE, 19803
Phone (302) 320-9771
Fax (302) 623-7964
Enumeration date Oct 17, 2011
Last updated in NPPES Jan 13, 2025

Taxonomy & licenses

103T00000X Psychologist Behavioral Health & Social Service Providers · License B1-0011487 (DE) Primary
103T00000X Psychologist Behavioral Health & Social Service Providers · License PS017269 (PA) Secondary
PSYD · Doctor of Psychology: A clinical doctorate in psychology focused on professional practice. About the PSYD credential

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

What is the NPI number for Michael Williston?
The National Provider Identifier (NPI) for Michael Williston is 1093090474, a Type 1 (individual) record in the CMS NPPES registry.
Where does Michael Williston practice?
The practice location on file with NPPES is in Wilmington, DE. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-01-13.