Chester T. Gregson
Marriage & Family Therapist · Ontario, CA
Chester T. Gregson is a marriage & family therapist with a practice address in Ontario, California, and NPI 1073633731, issued on Mar 29, 2007. Check the license (California 38663, as entered in NPPES) with the California board that licenses this profession; the federal record below is the public data PlainDoctor holds for this provider.
- Name
- Chester T. Gregson
- Primary taxonomy
- Marriage & Family Therapist 106H00000X
- License number
- 38663 CA
Self-reported in NPPES; status is on the state search - Practice location
- 3200 E Guasti RD, Ontario, CA 91761
- Phone
- (619) 639-9730
- Enumerated
- Mar 29, 2007
- Record last updated
- Aug 4, 2025
- Entity
- Type 1 · individual
8 nearest marriage & family therapist records → All 59,889 in California → Look up another NPI →
Also registered at 3200 E Guasti RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Kristofer Anderson, MFTMarriage & Family Therapist1245510353
- Jaycee BarhamBehavior Technician1265100515
- Erika ChanBehavior Technician1922672906
- Michael Marshall, APRN, PMHNPPsychiatric/Mental Health Nurse Practitioner1245563543
- Lorena MartinMarriage & Family Therapist1588854590
- Briana Perez, LCSWClinical Social Worker1497424964
Verify Chester T. Gregson in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich California board licenses this profession
Search for license 38663Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Chester T. Gregson among 59,889 marriage & family therapist records in California
Chester T. Gregson is one of 59,889 marriage & family therapist records with a practice address in California. 4% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does not. Its NPI, issued in 2007, is newer than 7% of them.
- NPI issued2007 · 7% of these records are older, 77% newer
- In a Medicare fileNo · 4% of these records are
- In the CMS Doctors and Clinicians fileNo · 8% of these records are
- Record last updated2025 · 50% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 106H00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
169 marriage & family therapist records list a practice address in Ontario
They are 169 of the 5,375 NPPES records with a practice address in Ontario, and 59,889 marriage & family therapist records in California. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.
All 59,889 in California → Every provider in Ontario → Marriage & Family Therapist nationwide →
The 8 marriage & family therapist records with the nearest ZIP codes
- Kristofer Anderson, MFTOntario, CA 917611245510353
- Kelli Clayton, MS, LMFTOntario, CA 917611922263250
- Richard Croyt, LMFTOntario, CA 917611639212152
- Savina Dias, LMFTOntario, CA 917611598916066
- Virginia Escoto-Gonzalez, LMFTOntario, CA 917611548403322
- Charolette Lewis, PH.D. LMFTOntario, CA 917611912047580
- Lorena MartinOntario, CA 917611588854590
- Stacie Pasimio, LMFTOntario, CA 917611346546157
Common questions
What is Chester T. Gregson's NPI number?
Chester T. Gregson's National Provider Identifier (NPI) is 1073633731, issued on Mar 29, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Chester T. Gregson located?
The NPPES record lists a practice address at 3200 E Guasti RD, Ontario, CA, 91761. Phone: (619) 639-9730. Providers update this record themselves, so call before visiting.
How can I verify Chester T. Gregson's license?
NPPES lists California license number 38663, as entered by the provider. Search the California board that licenses this profession; the NPPES record confirms identity only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.