Doctor profile · Federal record

Dr. William Tseng, M.D.

Surgical Oncology Physician (CMS: Surgical Oncology) · Surgery Physician · Arcadia, CA

  • NPI 1417071242
  • Accepts Medicare
  • 22 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 3 locations .

NPPES Updated May 11, 2026
Primary practice
301 W Huntington Dr Ste 400
Arcadia, CA 910073471
(626) 218-9840
fax (626) 218-9860
Additional location
1500 Duarte RD
Duarte, CA 910103012
(626) 256-4673
Additional location
209 Fair Oaks Ave
South Pasadena, CA 910301814
(626) 396-2900
fax (626) 799-2889
Mailing address
Po Box 512185
Los Angeles, CA 900510185

Credentials & registration

NPPES · NUCC
NPI registered
March 2007 — 19 yrs on file
Profile last updated
June 8, 2022
Year of graduation
2004 — 22 yrs since
Specialty taxonomy
2086X0206X — NUCC code
State license (1)
California #A94446

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1417071242. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
84
Distinct HCPCS
3
Medicare allowed
$13,349
HCPCS Description Services Patients Avg allowed
99215 Established patient office or other outpatient visit, 40-54 minutes 37 29 $152
99205 New patient office or other outpatient visit, 60-74 minutes 32 32 $192
99214 Established patient office or other outpatient visit, 30-39 minutes 15 13 $104

In context: peer comparison

Among 1 peers in this city , average services per provider: 28. This provider delivers 3.0× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$2,706
Transactions
2
Manufacturers
2
Payer (manufacturer) Industry Txns Amount
Boehringer Ingelheim Pharmaceuticals, Inc. 1 $2,590.00
Aadi Bioscience, Inc. 1 $116.17

By nature of payment

Consulting Fee
$2,590
Food and Beverage
$116

Frequently asked questions

Auto-generated from federal data
What is Dr. William Tseng's medical specialty?
Dr. William Tseng practices Surgical Oncology Physician in Arcadia, CA.
Where does Dr. William Tseng practice?
Dr. William Tseng practices at 301 W Huntington Dr Ste 400, Arcadia, CA 910073471. Office phone: 6262189840.
What is Dr. William Tseng's NPI?
Dr. William Tseng's National Provider Identifier (NPI) is 1417071242, issued by NPPES.
Does Dr. William Tseng accept Medicare assignment?
Yes. Dr. William Tseng accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. William Tseng commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99215); New patient office or other outpatient visit (HCPCS 99205); Established patient office or other outpatient visit (HCPCS 99214). Source: CMS Medicare Physician & Other Practitioners file.