Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.

Dr. Warren Chow, MD

Individual provider Internal Medicine Physician · NPI 1093822017

Dr. Warren Chow, MD practises Medical Oncology in Orange, California. Graduated from R Franklin University of Med & SCI/Chicago Medical School in 1986, 40 years ago. Practices with Uc Regents, a 306-clinician group, accepts Medicare assignment and offers telehealth. Licensed in California.

Years since qualifying
40
Trained at
R Franklin University of Med & SCI/Chicago Medical School
Licensed in
CA
In the registry since
2006
Specialties on file
3
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Practice location Address checks out

101 The City Dr S
Orange, CA 92868-3201
Phone: (714) 456-5153
Fax: (714) 456-5280
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Hematology & Oncology Physician (primary) Taxonomy 207RH0003X · Licence G61354 (CA)
Internal Medicine Physician Taxonomy 207R00000X · Licence G61354 (CA)
Medical Oncology Physician Taxonomy 207RX0202X · Licence G61354 (CA)

Record details

NPI number1093822017
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedAugust 24, 2006
Last updated in NPPESMarch 25, 2025
Certification dateMarch 25, 2025

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyMEDICAL ONCOLOGY
Also practisesINTERNAL MEDICINE
Medical schoolR FRANKLIN UNIVERSITY OF MED & SCI/CHICAGO MEDICAL SCHOOL
Graduated 1986 (40 years in practice)
Group practice Uc Regents — 306 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients152
Services billed 607 a service is one billed item, such as a visit, a test or a procedure
Average patient age74

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $531 13 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Also affiliated with 1 hospital, which CMS identifies by certification number only.

Colleagues at Uc Regents

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 306 clinicians in the practice; 12 are shown here.

Other providers in Orange