William Hayes Armstrong, MD
Emergency Medicine Physician · Los Angeles, CA
William Hayes Armstrong, MD is an emergency medicine physician with a practice address in Los Angeles, California, and NPI 1245960293, issued on Jun 13, 2022. Check the license (California A200987, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- William Hayes Armstrong
- Credential
- MD
- Primary taxonomy
- Emergency Medicine Physician 207P00000X
- License numbers
- A200987 CA
0116037078 VA
Self-reported in NPPES; status is on the state search - Practice location
- 1401 S Grand Ave, Los Angeles, CA 90015
- Phone
- (213) 748-2411
- Enumerated
- Jun 13, 2022
- Record last updated
- Jun 29, 2025
- Medicare enrollment
- Enrolled (PECOS I20250714003037); accepts Medicare assignment
- Medical or professional school
- Virginia Commonwealth University, School Of Medicine, 2022
- Entity
- Type 1 · individual
8 nearest emergency medicine physician records → All 7,751 in California → Look up another NPI →
Also registered at 1401 S Grand Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Sahra AkbariStudent in an Organized Health Care Education/Training Program1255175386
- Susanne Alcudia, M.D.Student in an Organized Health Care Education/Training Program1700291739
Verify William Hayes Armstrong in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A200987Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
82% fewer Medicare Part D claims than the average emergency medicine physician in 2024
41 Medicare Part D claims for 33 beneficiaries, against an average of 226 among the 54,106 providers of this specialty who prescribed in Part D.
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.
Industry payments in 2024: $20.00
1 payment: education; the largest payer was Csl Behring. The 12,335 providers of this specialty with any payment received $953.79 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through one group practice
- Golden State Emergency Physicians IncLos Angeles, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William Hayes Armstrong among 7,751 emergency medicine physician records in California
William Hayes Armstrong, MD is one of 7,751 emergency medicine physician records with a practice address in California. 81% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2022, is newer than 95% of them.
- NPI issued2022 · 95% of these records are older, 2% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileYes · 59% of these records are
- Graduated2022 · median 2011 among the 4,560 with a school on file
- Record last updated2025 · 59% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207P00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Emergency Medicine Physician providers in California
There are 7,751 emergency medicine physician records in California.
All 7,751 in California → Every provider in Los Angeles → Emergency Medicine Physician nationwide →
The 8 emergency medicine physician records with the nearest ZIP codes
- Eric El-Tobgy, M.D.Los Angeles, CA 900151982655668
- Marc Futernick, M.D.Los Angeles, CA 900151528019239
- Robert Haas, D.O.Los Angeles, CA 900151942251509
- Stephen Liu, M.D.Los Angeles, CA 900151083666259
- Thomas Mailhot, M.D.Los Angeles, CA 900151134171978
- Susan Morris, D.O.Los Angeles, CA 900151447202957
- Kim Newton, M.D.Los Angeles, CA 900151932151362
- Deepti Pisupati, M.D.Los Angeles, CA 900151427009364
Common questions
What is William Hayes Armstrong, MD's NPI number?
William Hayes Armstrong, MD's National Provider Identifier (NPI) is 1245960293, issued on Jun 13, 2022. An NPI identifies a provider in billing; it is not a license.
Where is William Hayes Armstrong, MD located?
The NPPES record lists a practice address at 1401 S Grand Ave, Los Angeles, CA, 90015. Phone: (213) 748-2411. Providers update this record themselves, so call before visiting.
How can I verify William Hayes Armstrong, MD's license?
NPPES lists California license number A200987, 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 William Hayes Armstrong, MD prescribe under Medicare Part D?
In 2024, William Hayes Armstrong, MD had 41 Medicare Part D claims for 33 beneficiaries; the average among emergency medicine physician prescribers was 226. 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.