1. Home
  2. Directory
  3. California
  4. Upland
  5. Nurse Practitioner
  6. NPI Profile

WILLIAM A. SIA NP-C
NPI 1679063945
Nurse Practitioner - Family in Upland, CA

Active since May 13, 2018PECOS Enrolled
1382 E FOOTHILL BLVD, UPLAND, CA 91786(909) 982-6500(909) 920-0406 Get Directions Write a Review

NPPES record last updated: September 12, 2019. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Sep 12, 2019, May 13, 2018 (2 updates tracked since 2018).

About William A. Sia Np-c NPPES

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

WILLIAM A. SIA NP-C (NPI 1679063945) is an individual family provider in Upland, California, licensed in California (F03180293) and active in the NPI registry since May 2018. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1679063945
Entity TypeIndividualMale
Primary Taxonomy363LF0000X
Provider Legal NameWILLIAM A. SIACredential: NP-C
Location Address1382 E FOOTHILL BLVDUpland, CA 91786-4014
Mailing Address1365 Wickham CtSan Dimas, CA 91773-3862 · (626) 261-3175
Phone(909) 982-6500
Fax(909) 920-0406
Sole ProprietorNo
Enumeration DateMay 13, 2018
Last NPPES UpdateSeptember 12, 20192 updates tracked since enumeration
✔ NPI 1679063945 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNurse Practitioner · FamilyPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363LF0000X
License✔ Licensed in CA · F03180293
1382 E FOOTHILL BLVD, Upland, CA 91786
Open in Google Maps ↗

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

William A. Sia Np-c is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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.

Medicare Billing Reassignments

3

Medicare enrollment records show William Sia reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Clinica Medica Dr Juan Escobar Inc
36 mi
Internal Medicine
1711 W TEMPLE ST, SUITE # 3695
Los Angeles, CA 90026
  • Reassigned Medicare billing, California enrollment
  • 4 clinicians in this Medicare group
NPI 1942444286 (213) 989-0700
Beverly Community Clinic
37 mi
Federally Qualified Health Center (FQHC)
2252 BEVERLY BLVD STE 103
Los Angeles, CA 90057
  • Reassigned Medicare billing, California enrollment
  • 7 clinicians in this Medicare group
NPI 1144791500 (213) 674-7424
Hollywood Presbyterian Emergency Medical Associates, Inc.
38 mi
Emergency Medicine
1300 N VERMONT AVE
Los Angeles, CA 90027
  • Reassigned Medicare billing, California enrollment
  • 74 clinicians in this Medicare group
NPI 1972826931 (310) 321-0143

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 91786 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
$91.88 typical visit price
range $59.60 – $179.42
Typical copayment $22.97 (range $14.90 – $44.85)
Most-billed visit code 99203
Established Patient
$104.64 typical visit price
range $19.37 – $146.42
Typical copayment $26.16 (range $4.84 – $36.60)
Most-billed visit code 99214
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 4

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

INLAND CARDIOLOGY HEART FAILURE CLINIC
Internal Medicine (Cardiovascular Disease)
1382 E FOOTHILL BLVD
UPLAND, CA 91786
San Bernardino County (909) 982-6500
RUSHMI REEHAL PA-C
Physician Assistant
1382 E FOOTHILL BLVD
UPLAND, CA 91786
San Bernardino County (909) 982-6500
B DON AHN MD INC
Internal Medicine (Cardiovascular Disease)
1382 E FOOTHILL BLVD
UPLAND, CA 91786
San Bernardino County (909) 982-6500
PROHEALTH PARTNERS A MEDICAL GROUP INC
Internal Medicine (Cardiovascular Disease)
1382 E FOOTHILL BLVD
UPLAND, CA 91786
San Bernardino County (909) 982-6500

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 Sia's NPI number?

The NPI number for William Sia is 1679063945. It was assigned to this individual provider in the NPPES registry on May 13, 2018.

Where is William Sia located?

William Sia practices at 1382 E Foothill Blvd, Upland, CA 91786. The listed phone number is (909) 982-6500.

What is William Sia's specialty?

The primary specialty registered for this NPI is Nurse Practitioner, specializing in Family, with taxonomy code 363LF0000X.

Is William Sia enrolled in Medicare?

Yes. William Sia is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for William Sia's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Sia reassigns Medicare benefits to 3 organizations: Clinica Medica Dr Juan Escobar Inc (Los Angeles, CA), Beverly Community Clinic (Los Angeles, CA) and Hollywood Presbyterian Emergency Medical Associates, Inc. (Los Angeles, CA). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for William Sia's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for William Sia was last updated on September 12, 2019. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 7 years 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.