Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
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William Marrin, PHD

Individual provider Psychologist · NPI 1861493629

William Marrin, PHD is a Clinical Psychologist in Port Jefferson, New York. Qualified in 1984, 42 years ago. Practices as a sole proprietor and accepts Medicare assignment. Licensed in New York.

Years since qualifying
42
Licensed in
NY
In the registry since
2005
What do these letters mean?
PHD — Doctor of Philosophy
A research doctorate. In healthcare it usually sits alongside a clinical licence.

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Practice location Address checks out

200 Belle Terre Rd
Port Jefferson, NY 11777-1928
Phone: (631) 474-6000
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Psychologist (primary) Taxonomy 103T00000X · Licence 008777 (NY)

Record details

NPI number1861493629
Entity typeIndividual (Type 1)
GenderMale
Credentials PHD
Sole proprietorYes
NPI enumeratedAugust 2, 2005
Last updated in NPPESMay 5, 2011

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyCLINICAL PSYCHOLOGIST
Medical schoolOTHER
Graduated 1984 (42 years in practice)
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Other providers in Port Jefferson