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

Individual provider Mental Health Counselor · NPI 1831239037

Mr. Matthew Grelling, MA, MFT is a Mental Health Counselor in Diamond Bar, California. Practices as a sole proprietor. Licensed in California.

Licensed in
CA
In the registry since
2007
What do these letters mean?
MA — Master of Arts
A graduate arts degree.
MFT — Marriage and Family Therapist
A therapist who treats couples and families.

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Practice location Address checks out

1111 Grand Ave Ste J
Diamond Bar, CA 91765-4172
Phone: (951) 505-0019
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Mental Health Counselor (primary) Taxonomy 101YM0800X · Licence MFT 35675 (CA)

Record details

NPI number1831239037
Entity typeIndividual (Type 1)
GenderMale
Credentials MA , MFT
Sole proprietorYes
NPI enumeratedFebruary 7, 2007
Last updated in NPPESJuly 8, 2007

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