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Mary Todd Williamson, PHD

Clinical Psychologist in Columbia, MO · enumerated 2006.

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

National Provider Identifier

1821041021

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Registry record

Entity type Individual (Type 1)
Name Mary Todd Williamson
Credential PHD
Sex Female
Practice address 3217 S Providence Rd, Columbia, MO, 65203
Phone (573) 884-7733
Fax (573) 884-5559
Enumeration date May 18, 2006
Last updated in NPPES Sep 25, 2008

Taxonomy & licenses

103TC0700X Clinical Psychologist Behavioral Health & Social Service Providers · License PY01775 (MO) Primary
PHD · Doctor of Philosophy: A doctoral degree; in healthcare often held by clinical psychologists and researchers. About the PHD credential

Other identifiers

Identifier Type State Issuer
680007308 Other MO RR MEDICARE
P00415787 Other MO RAILROAD MEDICARE
498143601 Medicaid MO -

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 Mary Williamson practice?
The practice location on file with NPPES is in Columbia, MO. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mary Williamson?
The National Provider Identifier (NPI) for Mary Williamson is 1821041021, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-09-25.