Physician Assistants in Ontario, CA
Browse 37 Physician Assistant providers listed in NPPES with a practice address in Ontario, California.
How Ontario compares with the U.S.
Ontario has 20 Physician Assistants per 100,000 residents, about 42% of the U.S. rate of 49.
That is 37 active Physician Assistants with a practice address in Ontario, for a population of 180,547.
The California rate is 37 per 100,000 residents.
What these numbers mean
Clinicians per 100,000 residents compares places of different sizes. We count active clinicians who list a practice address in the area in the federal NPI registry (NPPES) and divide by the number of people who live there, according to the U.S. Census Bureau. The U.S. rate is the same calculation for the whole country.
A higher number does not mean it is easier to get an appointment, that wait times are shorter, or that care is better. It also does not show how many clinicians are accepting new patients or which insurance plans they take. A lower number does not by itself mean there is a shortage.
City counts use the city name in each clinician's practice address. That postal city can cover a larger or smaller area than the city limits the Census Bureau uses for population, and many clinicians list only one address even if they work in several places.
93% of Physician Assistants in Ontario listed in the CMS Medicare file (14 of 15) accept Medicare assignment. That is similar to the California share of 92%.
Only 15 of 37 active Physician Assistants in Ontario appear in the CMS Medicare file, so this share describes that smaller group.
What is Medicare assignment?
A clinician who accepts Medicare assignment agrees to take the Medicare-approved amount as full payment for services that Original Medicare covers. You usually still pay your deductible and coinsurance. This comes from the CMS Doctors and Clinicians file and applies to Original Medicare only. Medicare Advantage plans have their own provider networks. It does not show whether a clinician is taking new patients.
Some clinicians are listed as "may accept assignment," which means they can decide case by case. Clinicians without an assignment flag, or who are not in the CMS file, are not counted as accepting assignment. That does not mean they refuse Medicare. Ask the office before your visit.
20% of Physician Assistants in Ontario listed in the CMS Medicare file (3 of 15) have a CMS telehealth indicator, meaning their recent Medicare claims include telehealth services. That is lower than the California share of 28%.
About the telehealth indicator
The telehealth indicator comes from CMS. It marks clinicians whose recent paid Medicare claims include services delivered by telehealth. It means a clinician has provided some services by telehealth, not that every visit can be done online. A clinician without the indicator may still offer telehealth, for example to patients who are not on Medicare. Ask the office which visits can be done by video or phone.
These figures summarize public federal data. They do not measure quality of care, appointment availability, or whether a clinician accepts your insurance or new patients. Registry addresses can be out of date. Please confirm details directly with the office and your plan. This information is not medical advice.
Prepared by T-MedInfo from NPPES, CMS and U.S. Census Bureau data. Questions or corrections: support@true-medinfo.com ยท Methodology
Sources: Clinician counts and practice addresses: NPPES NPI Registry, Centers for Medicare & Medicaid Services (CMS), data as of August 2026. Medicare assignment and telehealth indicators: CMS Doctors and Clinicians National Downloadable File. Population: U.S. Census Bureau, American Community Survey 2020-2024 5-Year Estimates, Table B01003 (Total Population).
Physician Assistant Medicare (PECOS) Enrollment & Ordering Eligibility
Medicare enrollment and order/referring eligibility listed by CMS for Physician Assistant practitioners in Ontario, CA
Linden Batiste , PA-C
Physician Assistant
Kevin Bell
Physician Assistant
Katherine M Beltre Espinosa
Physician Assistant
Debra Ann Blanco , PA-C
Physician Assistant
Lauren Michelle Bolda
Physician Assistant
Wei Hang Chen-Wu
Physician Assistant
Hanna Choi , PHYSICIAN ASSISTANT
Physician Assistant
Shawn Chowdhury , PA
Physician Assistant
Charmaine Yolanda Collins-Cepeda , PA-C
Physician Assistant
Marcus Eugene Harris , PA-C
Physician Assistant
Sepideh Homayoni , PA-C
Physician Assistant
Britney Elise Kaufman , PA
Physician Assistant
Carol Haein Kwak , PA-C
Physician Assistant
Lan Kim Lam , PA-C
Physician Assistant
Tahnee Lilly
Physician Assistant
Erin Marie Pascale , PA
Physician Assistant
Robert Pedroza
Physician Assistant
Nicholas Joseph Pena , PA-C
Physician Assistant
Jesus Perea Ochoa
Physician Assistant
Ronald James Pratt , PA-C
Physician Assistant
Frequently Asked Questions about Physician Assistant in Ontario
Each practitioner profile shows the NUCC taxonomy code and any state license number the practitioner reported to NPPES, plus a link to the California licensing board lookup. NPPES entries are self-reported; current license status is published only by the state board.
This list shows NPI records that are active in NPPES. A deactivated NPI keeps its profile with the deactivation date and practice history; find it with the site search by name or NPI number.
Other Specialties in Ontario
Physician Assistants in Other California Cities
Cities with the most listed practitioners first.