William J Tsai MD Inc
NPI 1114277738 · Internal Medicine Physician · Irvine, CA
Enrolled with Medicare as Part B Supplier - Clinic/Group Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William J Tsai MD Inc is a Internal Medicine Physician organization in Irvine, CA (NPI 1114277738).
Provider details
- NPI number
- 1114277738
- Entity type
- Organization
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Organization subpart
- No
- Authorized official
- William Tsai, Pres/Ceo(949) 955-0202
- License
- A71679 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
13 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2012-09-11
- Last updated
- 2012-09-11
Frequently asked questions
- What is William J Tsai MD Inc's NPI number?
- William J Tsai MD Inc's National Provider Identifier (NPI) is 1114277738, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What type of organization is William J Tsai MD Inc?
- William J Tsai MD Inc is classified in the NPPES registry as Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is William J Tsai MD Inc located?
- William J Tsai MD Inc's practice location on file with NPPES is 19742 Macarthur Blvd, Irvine, CA 92612-2432.
- What is William J Tsai MD Inc's phone number?
- The practice phone number listed in the NPPES registry for William J Tsai MD Inc is (949) 955-0202.
- Does William J Tsai MD Inc accept Medicare?
- William J Tsai MD Inc is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Who is the authorized official for William J Tsai MD Inc?
- The authorized official listed on William J Tsai MD Inc's NPPES record is William Tsai, Pres/Ceo. The authorized official registers and maintains the organization's NPI and is not necessarily its owner.
- Is William J Tsai MD Inc's NPI active?
- Yes — William J Tsai MD Inc's NPI (1114277738) is active in the NPPES registry as of the last update on 2012-09-11.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.