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

Dr. Mark Stanley Jesinoski, PHD

Psychologist in Oceanside, CA · enumerated 2018 · practices at True North Psychological Services, Inc..

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

National Provider Identifier

1255829727

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Registry record

Entity type Individual (Type 1)
Name Dr. Mark Stanley Jesinoski
Credential PHD
Sex Male
Practice address Oceanside, CA, 92058
Phone (760) 810-1440
Enumeration date Apr 30, 2018
Last updated in NPPES Apr 30, 2018

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 26433 (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

Is NPI 1255829727 active?
Yes, as of the latest NPPES snapshot, NPI 1255829727 is active (record last updated 2018-04-30).
How do I verify Mark Jesinoski's NPI record?
Cross-check NPI 1255829727 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2018-04-30.