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

Individual provider Internal Medicine Physician · NPI 1952356560

Dr. William J Tsai, MD is an Internal Medicine in Irvine, California. Qualified in 1997, 29 years ago. Practices as a sole proprietor, accepts Medicare assignment and offers telehealth. Licensed in California.

Years since qualifying
29
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

19742 Macarthur Blvd Ste 101
Irvine, CA 92612-2432
Phone: (949) 955-0202
Fax: (949) 955-0203
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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 · Licence A71679 (CA)

Record details

NPI number1952356560
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorYes
NPI enumeratedMay 23, 2006
Last updated in NPPESJuly 16, 2010

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Medical schoolOTHER
Graduated 1997 (29 years in practice)
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations2 on file with Medicare

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