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Marissa L. Williamson, BCBA

Marissa L. Williamson is a Behavior Analyst provider (Behavior Analyst) practicing in Thousand Oaks, CA, registered in the NPPES registry with NPI 1942512496 since 2010.

✓ Active NPI ✓ Valid NPI checksum Sole proprietor

NPI 1942512496
Entity type Individual (Type 1)
Name Marissa L. Williamson
Credential BCBA
Sex Female
Practice address Thousand Oaks, CA, 91360
Phone 8772629133
Fax 8772629134
Enumeration date 2010-07-12
Last updated in NPPES 2010-07-12

Street address withheld — NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

Taxonomy code Specialty Primary License State
103K00000X Behavior Analyst Primary 1-09-6790
Copy-ready billing details
Provider: Marissa Williamson, BCBA
NPI: 1942512496
Taxonomy: 103K00000X (Behavior Analyst)
Address: Thousand Oaks, CA, 91360

Other providers at this practice address

NPI Name Type Specialty Location
1407867757 Lisa White Individual Marriage & Family Therapist Thousand Oaks, CA
1548323850 Shirley Glynn Individual Clinical Psychologist Thousand Oaks, CA
1629103254 Mindy Gillihan Individual Marriage & Family Therapist Thousand Oaks, CA
1124158035 Aileen Nealie Individual Marriage & Family Therapist Thousand Oaks, CA
1437270964 Barbara Porush Individual Marriage & Family Therapist Thousand Oaks, CA
1003123845 David Scrivner Individual Marriage & Family Therapist Thousand Oaks, CA
1629370630 Shannon Duncan Individual Behavior Analyst Thousand Oaks, CA
1215239074 Laura Dodds Individual Behavior Analyst Thousand Oaks, CA

Verify this record

Cross-check NPI 1942512496 against the authoritative CMS record: view Marissa L. Williamson on the official NPPES registry .

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes — even if the provider moves or changes specialty. Read the full guide or validate an NPI number.

Frequently asked questions

How do I verify Marissa Williamson's NPI record?
Cross-check NPI 1942512496 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1942512496 active?
Yes — as of the latest NPPES snapshot, NPI 1942512496 is active (record last updated 2010-07-12).

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2010-07-12.