5,893 NPI-registered providers practice in Ontario, California. Pick another city in the rail, or open the full search to filter by specialty and credential.
| Provider | Specialty | Location | NPI |
|---|---|---|---|
| 24/7 Hospice | Community Based Hospice Care Agency | Ontario, CA | 1669710760 |
| 3lmc Premier Healthcare LLC | Home Health Agency | Ontario, CA | 1780097931 |
| 4 U Medical Transit |
| Non-emergency Medical Transport (VAN) |
| Ontario, CA |
| 1114473709 |
| 888 Hbreal Estate Investments Corp | Customized Equipment (DME) | Ontario, CA | 1407575814 |
| A&g Health Services Inc | Physical Therapy Clinic/Center | Ontario, CA | 1396891610 |
| A&i Advisors Inc | Local Education Agency (LEA) | Ontario, CA | 1912238361 |
| A&l Rehab Specialist Inc | Durable Medical Equipment & Medical Supplies | Ontario, CA | 1881472447 |
| Aarb Medical & Healthcare Services Inc | Health Service Clinic/Center | Ontario, CA | 1952023897 |
| Aaron ZiaDC | Chiropractor | Ontario, CA | 1679774236 |
| Abbas Al JiduiDDS | General Practice Dentistry | Ontario, CA | 1558498162 |
| Abby Armagost | Behavior Analyst | Ontario, CA | 1033938352 |
| Abid Hameed Khan MD Professional Corporation | Nephrology Physician | Ontario, CA | 1518153733 |
| Abid KhanM.D. | Nephrology Physician | Ontario, CA | 1326184524 |
| Ablossom Health Care | Home Health Agency | Ontario, CA | 1134971922 |
| Academy Medical Equipment, Inc. | Durable Medical Equipment & Medical Supplies | Ontario, CA | 1891123790 |
| Accentcare Health Management, Inc. | Case Management Agency | Ontario, CA | 1184010431 |
| Accuquest Hearing Centers LLC | Hearing and Speech Clinic/Center | Ontario, CA | 1629409842 |
| Ace Medical Transportation, LLC | Non-emergency Medical Transport (VAN) | Ontario, CA | 1750668554 |
| Acevedo Dental Corp | Oral and Maxillofacial Surgery Clinic/Center | Ontario, CA | 1497309306 |
| Act Family Counseling Incorporated | Marriage & Family Therapist | Ontario, CA | 1831494350 |
| Ada Mbai | Medical-Surgical Registered Nurse | Ontario, CA | 1053125583 |
| Adam MalikDO | Psychiatry Physician | Ontario, CA | 1407434665 |
| Adam Martinez | Behavior Technician | Ontario, CA | 1083225668 |
| Adebukola OlusanyaNURSE PRACTITIONER | Family Nurse Practitioner | Ontario, CA | 1710441720 |
| Adelaida a ZavalaRN | Registered Nurse | Ontario, CA | 1235702804 |
| Adelbert VuPT | Physical Therapist | Ontario, CA | 1376203372 |
| Adil Al-HashimiDDS | Dentist | Ontario, CA | 1285943597 |
| Aditi PareyDDS | Dentist | Ontario, CA | 1558036053 |
| Adni Cs LLC | Clinic/Center | Ontario, CA | 1972465664 |
| Adolf0 MejiaM.ED. | Behavior Analyst | Ontario, CA | 1538605944 |
| Adriana RivasBCBA | Behavior Analyst | Ontario, CA | 1720606775 |
| Adrienne Witherspoon | Social Worker | Ontario, CA | 1215617048 |
| Advance Hospice Services, Inc. | Community Based Hospice Care Agency | Ontario, CA | 1306265863 |
| Advocates for Medical Expansion | Voluntary or Charitable Agency | Ontario, CA | 1073494183 |
| Aegis Medical Systems, Inc. | Case Management Agency | Ontario, CA | 1417118282 |
| Aegis Treatment Centers, LLC | Methadone Clinic | Ontario, CA | 1013353861 |
| Aegis Treatment Centers, LLC | Methadone Clinic | Ontario, CA | 1275698615 |
| Aero Mobility, Inc. | Prosthetic/Orthotic Supplier | Ontario, CA | 1043101165 |
| Afa Consulting Corporation | Durable Medical Equipment & Medical Supplies | Ontario, CA | 1093811143 |
| Ageless Health Group, a Professional Corp Nursing | Multi-Specialty Clinic/Center | Ontario, CA | 1033829478 |
| Agha HayderNURSE PRACTITIONER | Nurse Practitioner | Ontario, CA | 1447660873 |
| Aht Services LLC | Non-emergency Medical Transport (VAN) | Ontario, CA | 1871092270 |
| Aidan Guerrero | Addiction (Substance Use Disorder) Counselor | Ontario, CA | 1942756226 |
| Aileen CastellanosAMFT | Marriage & Family Therapist | Ontario, CA | 1275188401 |
| Aja Plus Home Health Services, Inc | Home Health Agency | Ontario, CA | 1083945380 |
| Alabaster Medical Integrations | In Home Supportive Care Agency | Ontario, CA | 1649971342 |
| Alabaster Medical Integrations | Non-emergency Medical Transport (VAN) | Ontario, CA | 1770220410 |
| Alam & Elkhiar Chiropractic Professional Corporation | Occupational Health Chiropractor | Ontario, CA | 1669619607 |
| Alan KuoM.D. | Cardiovascular Disease Physician | Ontario, CA | 1699193391 |
| Alan Nguyen | Pharmacist | Ontario, CA | 1447038781 |
| Alba Delgadillo- Paramo | Marriage & Family Therapist | Ontario, CA | 1871919209 |
| Albert Balderas | Marriage & Family Therapist | Ontario, CA | 1518277821 |
| Alberto Guzman | Pharmacist | Ontario, CA | 1447972237 |
| Alberto MaldonadoBCBA | Behavior Analyst | Ontario, CA | 1821553033 |
| Aleida Murcia | Social Worker | Ontario, CA | 1225380975 |
| Alejandra Enriquez | Clinical Social Worker | Ontario, CA | 1265867261 |
| Alexander A. Galvan DMD | Dentist | Ontario, CA | 1609080316 |
| Alexander Castaneda | Health & Wellness Coach | Ontario, CA | 1881579407 |
| Alexandora Siporin | Pediatrics Physician | Ontario, CA | 1285807990 |
| Alexandra Engen | Addiction (Substance Use Disorder) Counselor | Ontario, CA | 1669918397 |
| Alexandra Interiano-OrozcoDNP FNP-C | Family Nurse Practitioner | Ontario, CA | 1144663873 |
| Alexandra RuizRBT | Behavior Technician | Ontario, CA | 1285171868 |
| Alexandra ValenciaFNP | Family Nurse Practitioner | Ontario, CA | 1659252476 |
| Alexandria MonicayoDC | Chiropractor | Ontario, CA | 1871337600 |
| Alexis HoffmanAMFT, APCC | Marriage & Family Therapist | Ontario, CA | 1700675246 |
| Alexis Rangel | Speech-Language Assistant | Ontario, CA | 1588595490 |
| Alexis Reyes | Family Nurse Practitioner | Ontario, CA | 1942933460 |
| Alexis RodriguezAPCC | Mental Health Counselor | Ontario, CA | 1760235550 |
| Alexzandria Haro | Student in an Organized Health Care Education/Training Program | Ontario, CA | 1184357600 |
| Alfredo SercadoPTA/COTA | Physical Therapy Assistant | Ontario, CA | 1982219341 |
| Ali Shahzad GhajarDDS | General Practice Dentistry | Ontario, CA | 1467504944 |
| Ali Shahzad- Ghajar DDS Inc | Dentist | Ontario, CA | 1801038252 |
| Alice Pruitt | Addiction (Substance Use Disorder) Counselor | Ontario, CA | 1568969269 |
| Alicia MarinD.C. | Chiropractor | Ontario, CA | 1598812190 |
| Alicia Prieto | Behavior Technician | Ontario, CA | 1679387500 |
| Alicia Smith | Behavior Analyst | Ontario, CA | 1710265228 |
| Alicia Velasquez | Dental Assistant | Ontario, CA | 1275867327 |
| Aline ScottLMFT | Marriage & Family Therapist | Ontario, CA | 1982104998 |
| Alisha Doussett | Speech-Language Assistant | Ontario, CA | 1447100227 |
| Alisha FlemingBCBA | Behavior Analyst | Ontario, CA | 1174911523 |
| All Adl Care LLC | Respite Care | Ontario, CA | 1437532041 |
| Allan DizonMPT | Orthopedic Physical Therapist | Ontario, CA | 1023146461 |
| Allan ManioPHARMD | Pharmacist | Ontario, CA | 1538519780 |
| Allcare Health Services LLC | Home Health Agency | Ontario, CA | 1144838012 |
| Allcare Health Services, Inc | Home Health Agency | Ontario, CA | 1164510947 |
| Alliance Medical Equipment & Resp. Pharmacy, Inc | Pharmacy | Ontario, CA | 1699730291 |
| Allison MataBCBA | Behavior Analyst | Ontario, CA | 1760918643 |
| Allison Redondo Lugo | Family Nurse Practitioner | Ontario, CA | 1386234789 |
| Allison WingLCSW | Clinical Social Worker | Ontario, CA | 1497024483 |
| Alondra Razo Chavez | Student in an Organized Health Care Education/Training Program | Ontario, CA | 1922837269 |
| Alpha Home Health | Home Health Agency | Ontario, CA | 1366777567 |
| Alyssa HarperMS | Health & Wellness Coach | Ontario, CA | 1427916592 |
| Alyssa Marie ValerioRN | School Registered Nurse | Ontario, CA | 1942015508 |
| Alyssa Panjaitan | Speech-Language Pathologist | Ontario, CA | 1144701939 |
| Alyssa Quinones | Behavior Analyst | Ontario, CA | 1033768247 |
| Alyssa Villalpando | Student in an Organized Health Care Education/Training Program | Ontario, CA | 1154198174 |
| Alyzah DalnayOTR/L | Occupational Therapist | Ontario, CA | 1144920075 |
| Amairany Martinez | Behavior Analyst | Ontario, CA | 1013418250 |
| Amaiyrany Ramos Talavera | Behavior Technician | Ontario, CA | 1629586466 |
| Amanda Aguilar | Behavior Technician | Ontario, CA | 1235977869 |
Source: CMS NPPES Data Dissemination (June 2026).
