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

William C Sim MD

Organization Internal Medicine Physician · NPI 1184431181

William C Sim MD is an Internal Medicine Physician in Fullerton, California. Registered with an NPI since 2024.

In the registry since
2024

Practice location Address checks out

3111 Santa Rosa Pl
Fullerton, CA 92835-1522
Phone: (562) 237-8761
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X

Record details

NPI number1184431181
Entity typeOrganization (Type 2)
Organization subpartNo
Authorized official William Sim — President · (562) 237-8761
NPI enumeratedDecember 12, 2024
Last updated in NPPESDecember 12, 2024
Certification dateDecember 12, 2024
Mailing address3111 Santa Rosa Pl, Fullerton, CA 92835-1522

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