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Mrs. Gillian Marie Williams, PNP

Pediatric Nurse Practitioner in Upland, CA · enumerated 2014.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1730589169

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Registry record

Entity type Individual (Type 1)
Name Mrs. Gillian Marie Williams
Credential PNP
Sex Female
Practice address 440 N Mountain Ave, Suite 112, Upland, CA, 91786
Phone (909) 931-1313
Fax (909) 920-3883
Enumeration date Sep 4, 2014
Last updated in NPPES Sep 4, 2014

Taxonomy & licenses

163W00000X Registered Nurse Nursing Service Providers · License 664000 (CA) Secondary
363LP0200X Pediatric Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 22163 (CA) Primary

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Is NPI 1730589169 active?
Yes, as of the latest NPPES snapshot, NPI 1730589169 is active (record last updated 2014-09-04).
How do I verify Gillian Williams's NPI record?
Cross-check NPI 1730589169 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2014-09-04.