William Loo
Physician Assistant · Pomona, CA
William Loo is a physician assistant with a practice address in Pomona, California, and NPI 1427887660, issued on Jul 27, 2024. Check the license (California 65690, as entered in NPPES) with the California board that licenses this profession; the Medicare figures below come from public CMS files.
- Name
- William Loo
- Primary taxonomy
- Physician Assistant 363A00000X
- License number
- 65690 CA
Self-reported in NPPES; status is on the state search - Practice location
- 450 E 2ND St, Pomona, CA 91766
- Phone
- (909) 469-5335
- Enumerated
- Jul 27, 2024
- Record last updated
- Jan 16, 2025
- Medicare enrollment
- Enrolled (PECOS I20251008001098); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest physician assistant records → All 14,451 in California → Look up another NPI →
Also registered at 450 E 2ND St
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Lara McKennon, PAPhysician Assistant1891614632
- Rinko YukiPhysician Assistant1447822895
Verify William Loo in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich California board licenses this profession
Search for license 65690Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Bills Medicare through one group practice
- West Coast Wound And Skin Care IncBurbank, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William Loo among 14,451 physician assistant records in California
William Loo is one of 14,451 physician assistant records with a practice address in California. 75% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2024, is newer than 87% of them.
- NPI issued2024 · 87% of these records are older, 7% newer
- In a Medicare fileYes · 75% of these records are
- In the CMS Doctors and Clinicians fileYes · 50% of these records are
- Graduated2024 · median 2018 among the 7,214 with a school on file
- Record last updated2025 · 40% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 363A00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
186 physician assistant records list a practice address in Pomona
They are 186 of the 5,102 NPPES records with a practice address in Pomona, and 14,451 physician assistant records in California.
All 14,451 in California → Every provider in Pomona → Physician Assistant nationwide →
The 8 physician assistant records with the nearest ZIP codes
- Lidia AlvarezPomona, CA 917661477004265
- Parvaneh Darvish, P.A.-CPomona, CA 917661295946697
- Timothy Foster, PAPomona, CA 917661427505296
- Hailey GarrisonPomona, CA 917661629590732
- Cynthia Hoang, PA-CPomona, CA 917661245548874
- Jonathan LeePomona, CA 917661609329424
- Miguel Medina, PACPomona, CA 917661447232640
- Reynaldo Obrero, P.A.-CPomona, CA 917661275784852
Common questions
What is William Loo's NPI number?
William Loo's National Provider Identifier (NPI) is 1427887660, issued on Jul 27, 2024. An NPI identifies a provider in billing; it is not a license.
Where is William Loo located?
The NPPES record lists a practice address at 450 E 2ND St, Pomona, CA, 91766. Phone: (909) 469-5335. Providers update this record themselves, so call before visiting.
How can I verify William Loo's license?
NPPES lists California license number 65690, as entered by the provider. Search the California board that licenses this profession; the NPPES record confirms identity 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.