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CHESTER T GREGSON
NPI 1073633731
Marriage & Family Therapist in Ontario, CA

Active since March 29, 2007
3200 E GUASTI RD, ONTARIO, CA 91761(619) 639-9730 Get Directions Write a Review

NPPES record last updated: August 4, 2025. Verified against the NPPES registry weekly; last sync: July 26, 2026.

Record update history: Aug 4, 2025, Jan 20, 2022, Dec 30, 2020 (3 updates tracked since 2020).

About Chester T Gregson NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

CHESTER T GREGSON (NPI 1073633731) is an individual marriage & family therapist in Ontario, California, licensed in California (38663) and active in the NPI registry since March 2007.

NPPES Registry Identity

NPI1073633731
Entity TypeIndividualMale
Primary Taxonomy106H00000X
Provider Legal NameCHESTER T GREGSON
Location Address3200 E GUASTI RDOntario, CA 91761-8660
Mailing AddressPo Box 713Coarsegold, CA 93614-0713 · (559) 676-7180
Phone(619) 639-9730
Sole ProprietorNo
Enumeration DateMarch 29, 2007
Last NPPES UpdateAugust 4, 20253 updates tracked since enumeration
NPPES CertifiedAugust 4, 2025
✔ NPI 1073633731 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyMarriage & Family TherapistBehavioral Health & Social Service Providers
Taxonomy Code106H00000X
License✔ Licensed in CA · 38663
Definition
A marriage and family therapist is a person with a master's degree in marriage and family therapy, or a master's or doctoral degree in a related mental health field with substantially equivalent coursework in marriage and family therapy, who receives supervised clinical experience, or a person who meets the state requirements to practice as a marriage and family therapist. A marriage and family therapist treats mental and emotional disorders within the context of marriage and family systems. A marriage and family therapist provides mental health and counseling services to individuals, couples, families, and groups.
3200 E GUASTI RD, Ontario, CA 91761
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Providence Health Plan.Insurance ›

Other Providers at the Same Location NPPES 14

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

JAIR WALKER
Behavior Technician
3200 E GUASTI RD
ONTARIO, CA 91761
San Bernardino County (909) 240-2565
4 U MEDICAL TRANSIT
Non-emergency Medical Transport (VAN)
3200 E GUASTI RD, SUITE 100
ONTARIO, CA 91761
San Bernardino County (844) 243-9988
MARSHALL ADVANCED NURSING PRACTICE PC
Nurse Practitioner (Psychiatric/Mental Health)
3200 E GUASTI RD
ONTARIO, CA 91761
San Bernardino County (909) 755-6610
RAVEN NALIKA ROSE LMFT
Marriage & Family Therapist
3200 E GUASTI RD
ONTARIO, CA 91761
San Bernardino County (909) 295-5805
KRISTOFER R ANDERSON MFT
Marriage & Family Therapist
3200 E GUASTI RD, SUITE 100-42
ONTARIO, CA 91761
San Bernardino County (909) 262-1768
MICHAEL MARSHALL APRN, PMHNP
Nurse Practitioner (Psychiatric/Mental Health)
3200 E GUASTI RD
ONTARIO, CA 91761
San Bernardino County (909) 755-6610
JAYCEE L BARHAM
Behavior Technician
3200 E GUASTI RD
ONTARIO, CA 91761
San Bernardino County (909) 240-2565
MARIA VARGAS LICENSED CLINICAL SOCIAL WORKER
Counselor (Mental Health)
3200 E GUASTI RD
ONTARIO, CA 91761
San Bernardino County (909) 963-6730

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Chester Gregson's NPI number?

The NPI number for Chester Gregson is 1073633731. It was assigned to this individual provider in the NPPES registry on March 29, 2007.

Where is Chester Gregson located?

Chester Gregson practices at 3200 E Guasti Rd, Ontario, CA 91761. The listed phone number is (619) 639-9730.

What is Chester Gregson's specialty?

The primary specialty registered for this NPI is Marriage & Family Therapist with taxonomy code 106H00000X.

What insurance does Chester Gregson accept?

Health plans from Providence Health Plan list Chester Gregson as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Chester Gregson was last updated on August 4, 2025. NPI Profile syncs with the weekly NPPES data releases published by CMS.