WILLIAM SHUN TZENG MD
NPI 1649809385
Internal Medicine in Hacienda Heights, CA
About William Shun Tzeng Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
WILLIAM SHUN TZENG MD (NPI 1649809385) is an individual internal medicine provider in Hacienda Heights, California, licensed in California (A187692) and active in the NPI registry since April 2020. He is enrolled in Medicare PECOS, maintains a secondary practice location in Monterey Park, and is a graduate of Washington University School Of Medicine (2020).
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Location 1
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
William Shun Tzeng Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.
Medicare Billing Reassignment
Medicare enrollment records show William Tzeng reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Hacienda Heights, CA 91745
- Reassigned Medicare billing, California enrollment
- 2 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Areas of Expertise CMS Part B claims 3
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
Physician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 91745 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Medicare Quality Performance CMS QPP · MIPS
Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.
Other Providers at the Same Location NPPES 2
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
HACIENDA HEIGHTS, CA 91745
Frequently Asked Questions NPPES & CMS
Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.
What is William Tzeng's NPI number?
The NPI number for William Tzeng is 1649809385. It was assigned to this individual provider in the NPPES registry on April 4, 2020.
Where is William Tzeng located?
William Tzeng practices at 17170 Colima Rd Ste G, Hacienda Heights, CA 91745. The listed phone number is (626) 965-8202.
What is William Tzeng's specialty?
The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.
Is William Tzeng enrolled in Medicare?
Yes. William Tzeng is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.
Which organization bills Medicare for William Tzeng's services?
According to the CMS Revalidation Reassignment List (October 2026 release), William Tzeng reassigns Medicare benefits to Health Alliance Medical Group (Hacienda Heights, CA). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for William Tzeng's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
When was this NPI record last updated?
The NPPES record for William Tzeng was last updated on October 25, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 9 days ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.
# William Shun Tzeng, MD · NPI 1649809385
Internal Medicine physician in Hacienda Heights, California. Individual provider, active in the CMS NPPES registry since April 4, 2020.
## Identity
- **NPI:** 1649809385 (Entity type: Individual)
- **Enumerated:** April 4, 2020
- **Primary specialty:** Internal Medicine · taxonomy 207R00000X
- **State license:** A187692 (California)
- **Sole proprietor:** No
## Practice location
- **Address:** 17170 COLIMA RD STE G, Hacienda Heights, CA 91745-6771
- **Phone:** (626) 965-8202 · **Fax:** (626) 964-9893
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** Health Alliance Medical Group (NPI 1124248570, Hacienda Heights, CA), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Washington University School Of Medicine, class of 2020
## Record status
- **NPPES last updated:** October 25, 2026
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Source: [NPI Profile](https://npiprofile.com/npi/1649809385) · Data from the CMS NPPES public registry.