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

Diana Seif

Individual provider Mental Health Counselor · NPI 1942571344

Diana Seif is a Mental Health Counselor in Ontario, California. Practices as a sole proprietor. Registered with an NPI since 2012.

In the registry since
2012

Practice location Address checks out

1556 S Sultana Ave
Ontario, CA 91761-4238
Phone: (909) 418-6923
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Mental Health Counselor (primary) Taxonomy 101YM0800X

Record details

NPI number1942571344
Entity typeIndividual (Type 1)
GenderFemale
Sole proprietorYes
NPI enumeratedJanuary 18, 2012
Last updated in NPPESJanuary 18, 2012

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