NPI Portal NPI Lookup & Verification

Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Nathan H. Oliver

Clinical Social Worker in Pasadena, CA · enumerated 2008.

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

National Provider Identifier

1891944385

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Registry record

Entity type Individual (Type 1)
Name Nathan H. Oliver
Sex Male
Practice address Pasadena, CA, 91107
Phone (626) 296-8900
Enumeration date Sep 9, 2008
Last updated in NPPES Dec 12, 2023

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

104100000X Social Worker Behavioral Health & Social Service Providers · License ACSW96740 (CA) Secondary
1041C0700X Clinical Social Worker Behavioral Health & Social Service Providers · License ACSW96740 (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 1891944385 active?
Yes, as of the latest NPPES snapshot, NPI 1891944385 is active (record last updated 2023-12-12).
How do I verify Nathan Oliver's NPI record?
Cross-check NPI 1891944385 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 2023-12-12.