Cassidy Erbst
Cassidy Erbst is a Psychologist in Ontario, CA, registered under NPI 1003652520.
Getting there
Here is what surrounds this office in Ontario, based on OpenStreetMap data collected Oct 12, 2026. Parking is available about 0.26 mi away. There is EV charging 0.38 mi from the office — useful if you are driving in from out of town. The nearest transit stop is 0.49 mi away, served by Omni. If you arrive early, there is a coffee shop 0.39 mi away.
Getting here and what is nearby
Hotel Comfort Inn & Suites Near Ontario Airport 498 ft ~2 min
Parking 633 ft ~3 min
Parking 1,029 ft ~4 min
Restaurant TGI Fridays 0.23 mi ~5 min
3351 Centrelake Dr, Ontario
Restaurant Panda Inn 0.25 mi ~5 min
3223 Centrelake Dr, Ontario
Parking 0.26 mi ~6 min
Hotel Fairfield Inn Ontario 0.29 mi ~6 min
Restaurant Hamburger Mary's 0.36 mi ~8 min
EV charging 0.38 mi ~8 min
Hotel Hampton Inn by Hilton Ontario Airport 0.38 mi ~8 min
Coffee Klatch Coffee 0.39 mi ~8 min
951 North Haven Avenue, Ontario 91764
Mo-Fr 06:00-22:00; Sa 07:00-18:00; Su 07:30-15:00
Transit Omni 0.49 mi ~10 min
Grocery Stater Bros. 0.51 mi ~11 min
Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.
Credentials and Medicare
NPPES does not list a state licence number for this record. That is not unusual — organizations and some provider types are not required to file one. Verify current licensure with the relevant state board before care.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
What Psychologist covers
A psychologist is an individual who is licensed to practice psychology which is defined as the observation, description, evaluation, interpretation, and modification of human behavior by the application of psychological principles, methods, and procedures, for the purpose of preventing or eliminating symptomatic, maladaptive, or undesired behavior and of enhancing interpersonal relationships, work and life adjustment, personal effectiveness, behavioral health, and mental health. The practice of psychology includes, but is not limited to, psychological testing and the evaluation or assessment of personal characteristics, such as intelligence, personality, abilities, interests, aptitudes, and neuropsychological functioning; counseling, psychoanalysis, psychotherapy, hypnosis, biofeedback, and behavior analysis and therapy; diagnosis and treatment of mental and emotional disorder or disability, alcoholism and substance abuse, disorders of habit or conduct, as well as of the psychological aspects of physical illness, accident, injury, or disability; and psycheducational evaluation, therapy, remediation, and consultation. Psychological services may be rendered to individuals, families, groups and the public. NUCC Health Care Provider Taxonomy, code 103T00000X
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1003652520 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 3, 2024 |
| Last updated | Jul 3, 2024 |
| Status | Active |
| Sole proprietor | No |
| Gender | Female |
| Practice address |
3350 SHELBY ST STE 200 Ontario, CA 91764 (909) 935-2385 |
| Mailing address |
13312 RANCHERO RD STE 677 Oak Hills, CA 92344 |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 0 | 0 | 3 | 6 | 5 | 2 | 5 | 2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 3 | 5 | 4 | 5 | 4 |
Sum = 50 · next multiple of 10 = 50 · check digit = 0 · actual last digit = 0
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.