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

Timothy Euiwon Byun, MD

Individual provider Hematology & Oncology Physician · NPI 1871545012

Timothy Euiwon Byun, MD practises Hematology/Oncology in Orange, California. Graduated from Rush Medical College of Rush University in 1998, 28 years ago. Practices with Providence Medical Foundation, a 1,465-clinician group, works from 2 locations, accepts Medicare assignment and offers telehealth. Licensed in California.

Years since qualifying
28
Trained at
Rush Medical College of Rush University
Licensed in
CA
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

805 W La Veta Ave Ste 101
Orange, CA 92868-3928
Phone: (714) 835-1800
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 1010 W La Veta Ave, Orange, CA 92868-4300 — (714) 835-1800

Specialties & licences

Hematology & Oncology Physician (primary) Taxonomy 207RH0003X · Licence A70195 (CA)

Record details

NPI number1871545012
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedMay 16, 2006
Last updated in NPPESJune 4, 2024
Certification dateJune 4, 2024

Medicare enrollment

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

Medicare specialtyHEMATOLOGY/ONCOLOGY
Medical schoolRUSH MEDICAL COLLEGE OF RUSH UNIVERSITY
Graduated 1998 (28 years in practice)
Group practice Providence Medical Foundation — 1465 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations5 on file with Medicare

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 patients364
Services billed 16,511 a service is one billed item, such as a visit, a test or a procedure
Average patient age76

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 $5,560 275 payments · a meal or drink at a meeting or visit, not a fee
Education $23 1 payment · educational material or training, 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.

  • Providence St. Joseph Hospital Hospital · Orange, CA
  • Providence At Home With Compassus Home Health Orange County Home health agency · Anaheim, CA

Colleagues at Providence Medical Foundation

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 1465 clinicians in the practice; 12 are shown here.

Other providers in Orange