Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

William W. Yoon, DO

Individual provider Family Medicine Physician · NPI 1770650509

William W. Yoon, DO is a Family Medicine Physician in Fontana, California. Licensed in California. Registered with an NPI since 2006.

Licensed in
CA
In the registry since
2006
What do these letters mean?
DO — Doctor of Osteopathic Medicine
A fully licensed physician, trained like an MD with additional musculoskeletal training. Equivalent practice rights in all 50 states.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

9961 Sierra Ave
Fontana, CA 92335-6720
Phone: (909) 427-3910
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

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

Specialties & licences

Family Medicine Physician (primary) Taxonomy 207Q00000X · Licence 20A7753 (CA)

Record details

NPI number1770650509
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorNo
NPI enumeratedNovember 29, 2006
Last updated in NPPESNovember 30, 2021
Mailing address9961 Sierra Ave, Fontana, CA 92335-6720

Other providers in Fontana