Stephen Sam-Fong Chen, M.D.
Internal Medicine Physician · Downey, CA
Stephen Sam-Fong Chen, M.D. is an internal medicine physician with a practice address in Downey, California, and NPI 1083844179, issued on Jul 23, 2009. Check the license (California A108952, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Stephen Sam-Fong Chen
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A108952 CA
Self-reported in NPPES; status is on the state search - Practice location
- 9333 Imperial Highway, Downey, CA 90242
- Phone
- (562) 657-9000
- Enumerated
- Jul 23, 2009
- Record last updated
- Mar 7, 2023
- Medicare enrollment
- Enrolled (PECOS I20111020000026); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 9333 Imperial Highway
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify Stephen Sam-Fong Chen in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A108952Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
96% fewer Medicare Part D claims than the average internal medicine physician in 2024
141 Medicare Part D claims for 43 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.
Most prescribed
- Amlodipine Besylate31 claims
- Bisoprolol Fumarate15 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Bills Medicare through one group practice
- Southern California Permanente Medical GroupDowney, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Stephen Sam-Fong Chen among 17,696 internal medicine physician records in California
Stephen Sam-Fong Chen, M.D. is one of 17,696 internal medicine physician records with a practice address in California. 79% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2009, is newer than 60% of them.
- NPI issued2009 · 60% of these records are older, 37% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2008 · median 2004 among the 11,065 with a school on file
- Record last updated2023 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
114 internal medicine physician records list a practice address in Downey
They are 114 of the 3,607 NPPES records with a practice address in Downey, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in Downey → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Sohail Afra, M.D.Downey, CA 902421023125176
- Ron Chai, M.D.Downey, CA 902421447361316
- Ronald Collins, M.D.Downey, CA 902421235176181
- Rashmi Desai, M.D.Downey, CA 902421801990247
- Basuki Gunawan, M.D.Downey, CA 902421346352473
- Danese Hayes, M.D.Downey, CA 902421689786733
- Goethe Hsu, M.D.Downey, CA 902421386656726
- Diana Hsu, M.D.Downey, CA 902421720090137
Common questions
What is Stephen Sam-Fong Chen, M.D.'s NPI number?
Stephen Sam-Fong Chen, M.D.'s National Provider Identifier (NPI) is 1083844179, issued on Jul 23, 2009. An NPI identifies a provider in billing; it is not a license.
Where is Stephen Sam-Fong Chen, M.D. located?
The NPPES record lists a practice address at 9333 Imperial Highway, Downey, CA, 90242. Phone: (562) 657-9000. Providers update this record themselves, so call before visiting.
How can I verify Stephen Sam-Fong Chen, M.D.'s license?
NPPES lists California license number A108952, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Stephen Sam-Fong Chen, M.D. prescribe under Medicare Part D?
In 2024, Stephen Sam-Fong Chen, M.D. had 141 Medicare Part D claims for 43 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.