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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. William Christopher Corrado, PSY.D

Clinical Psychologist in Oak Brook, IL · enumerated 2007 · practices at Leyden Dupage Counseling Services.

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

National Provider Identifier

1629281720

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Registry record

Entity type Individual (Type 1)
Name Dr. William Christopher Corrado
Credential PSY.D
Sex Male
Practice address Oak Brook, IL, 60523
Phone (630) 368-9100
Enumeration date May 7, 2007
Last updated in NPPES Jul 5, 2018

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

103TC0700X Clinical Psychologist Behavioral Health & Social Service Providers · License PSY20779 (CA) Primary
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 William Corrado?
The National Provider Identifier (NPI) for William Corrado is 1629281720, a Type 1 (individual) record in the CMS NPPES registry.
Where does William Corrado practice?
The practice location on file with NPPES is in Oak Brook, IL. 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 2018-07-05.