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

Dr. Mary Maresh, PH.D.

Psychologist in Lancaster, CA · enumerated 2013.

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

National Provider Identifier

1740520261

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Registry record

Entity type Individual (Type 1)
Name Dr. Mary Maresh
Credential PH.D.
Sex Female
Practice address Lancaster, CA, 93536
Phone (661) 729-2000
Enumeration date Feb 20, 2013
Last updated in NPPES Feb 20, 2013

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

Taxonomy & licenses

103T00000X Psychologist Behavioral Health & Social Service Providers · License PSY15693 (CA) 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 Mary Maresh practice?
The practice location on file with NPPES is in Lancaster, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mary Maresh?
The National Provider Identifier (NPI) for Mary Maresh is 1740520261, 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 2013-02-20.