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WILLIAM LOO
NPI 1427887660
Physician Assistant in Pomona, CA

Active since July 27, 2024PECOS EnrolledAccepts Medicare Assignment
450 E 2ND ST, POMONA, CA 91766(909) 469-5335 Get Directions Write a Review

NPPES record last updated: January 16, 2025. Verified against the NPPES registry weekly; last sync: August 16, 2026.

About William Loo NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

WILLIAM LOO (NPI 1427887660) is an individual physician assistant in Pomona, California, licensed in California (65690) and active in the NPI registry since July 2024. He is enrolled in Medicare PECOS and is a graduate of Other (2024).

NPPES Registry Identity

NPI1427887660
Entity TypeIndividualMale
Primary Taxonomy363A00000X
Provider Legal NameWILLIAM LOO
Location Address450 E 2ND STPomona, CA 91766-1950
Mailing Address5757 Baldwin Ave Apt BTemple City, CA 91780-2644 · (626) 532-0078
Phone(909) 469-5335
Sole ProprietorNo
Medical School CMSOtherGraduated 2024
Enumeration DateJuly 27, 2024
Last NPPES UpdateJanuary 16, 2025
NPPES CertifiedJanuary 16, 2025
✔ NPI 1427887660 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPhysician AssistantPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363A00000X
License✔ Licensed in CA · 65690
Definition
A physician assistant is a person who has successfully completed an accredited education program for physician assistant, is licensed by the state and is practicing within the scope of that license. Physician assistants are formally trained to perform many of the routine, time-consuming tasks a physician can do. In some states, they may prescribe medications. They take medical histories, perform physical exams, order lab tests and x-rays, and give inoculations. Most states require that they work under the supervision of a physician.
450 E 2ND ST, Pomona, CA 91766
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

William Loo 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.

PECOS PAC ID8022515873
PECOS Enrollment IDI20251008001098
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 91766 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$96.36 typical visit price
range $62.96 – $187.60
Typical copayment $24.09 (range $15.74 – $46.90)
Most-billed visit code 99203
Established Patient
$77.96 typical visit price
range $20.84 – $153.61
Typical copayment $19.49 (range $5.21 – $38.40)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 5

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

VALERIE LEUNG PA
Physician Assistant
450 E 2ND ST
POMONA, CA 91766
Los Angeles County (909) 623-6116
CATHERINE KITYI YAW HUYNH PA-C
Physician Assistant
450 E 2ND ST
POMONA, CA 91766
Los Angeles County (909) 469-5378
ALICE KIM
Student in an Organized Health Care Education/Training Program
450 E 2ND ST
POMONA, CA 91766
Los Angeles County (909) 469-5378
RINKO YUKI
Physician Assistant
450 E 2ND ST
POMONA, CA 91766
Los Angeles County (909) 623-6116
LARA ALLISON MCKENNON PA
Physician Assistant
450 E 2ND ST
POMONA, CA 91766
Los Angeles County (909) 623-6116

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 Loo's NPI number?

The NPI number for William Loo is 1427887660. It was assigned to this individual provider in the NPPES registry on July 27, 2024.

Where is William Loo located?

William Loo practices at 450 E 2nd St, Pomona, CA 91766. The listed phone number is (909) 469-5335.

What is William Loo's specialty?

The primary specialty registered for this NPI is Physician Assistant with taxonomy code 363A00000X.

Is William Loo enrolled in Medicare?

Yes. William Loo 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.

When was this NPI record last updated?

The NPPES record for William Loo was last updated on January 16, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 months 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.