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Dr. Thomas A Mahan, PHD

Marriage & Family Therapist in Naperville, IL · enumerated 2006.

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

National Provider Identifier

1508922147

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Registry record

Entity type Individual (Type 1)
Name Dr. Thomas A Mahan
Credential PHD
Sex Male
Practice address 124 S Webster St, Suite 202, Naperville, IL, 60540
Phone (630) 913-1627
Fax (866) 850-1154
Enumeration date Dec 28, 2006
Last updated in NPPES Oct 27, 2009

Taxonomy & licenses

106H00000X Marriage & Family Therapist Behavioral Health & Social Service Providers · License 166-000634 (IL) Primary
PHD · Doctor of Philosophy: A doctoral degree; in healthcare often held by clinical psychologists and researchers. About the PHD 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

Where does Thomas Mahan practice?
The practice location on file with NPPES is in Naperville, IL. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Thomas Mahan?
The National Provider Identifier (NPI) for Thomas Mahan is 1508922147, a Type 1 (individual) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2009-10-27.