NPI Portal NPI Lookup & Verification

Quest Diagnostics LLC

Quest Diagnostics LLC is a healthcare organization registered as Clinical Medical Laboratory in Stamford, CT, holding Type 2 (organization) NPI 1780886333 since 2007. The authorized official on file is G Cartier, Vp of Billing.

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NPI 1780886333
Entity type Organization (Type 2)
Legal business name Quest Diagnostics LLC
Parent organization Quest Diagnostics Incorporated
Practice address 1250 SUMMER ST, SUITE 206, Stamford, CT, 06905
Phone 8778682191
Enumeration date 2007-06-05
Last updated in NPPES 2007-11-26

Authorized official

Name G Cartier
Title Vp of Billing
Phone 4846767731

Taxonomy & classification

Taxonomy code Specialty Primary License State
291U00000X Clinical Medical Laboratory Primary CT
Copy-ready billing details
Provider: Quest Diagnostics LLC
NPI: 1780886333
Taxonomy: 291U00000X (Clinical Medical Laboratory)
Address: 1250 SUMMER ST, SUITE 206, Stamford, CT, 06905

Providers at this address

NPI Name Type Specialty Location
1891785176 Greg Besson Individual Physical Therapist Stamford, CT
1033281456 Elissa Diamond Individual Chiropractor Stamford, CT
1174674519 David Israel Individual Clinical Psychologist Stamford, CT
1598817413 William Weiss Individual Physical Therapist Stamford, CT
1225162845 Joseph Brady Individual Social Worker Stamford, CT
1326240870 Marilyn Mcquade Individual Physical Therapist Stamford, CT
1134322506 Donald Wood Individual Physical Therapist Stamford, CT
1477734887 Emily Besson Individual Physical Therapist Stamford, CT

Verify this record

Cross-check NPI 1780886333 against the authoritative CMS record: view Quest Diagnostics LLC on the official NPPES registry .

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. Read the full guide or validate an NPI number.

Frequently asked questions

Who is the authorized official for Quest Diagnostics LLC?
NPPES lists G Cartier (Vp of Billing) as the authorized official for this organization.
What is the NPI number for Quest Diagnostics LLC?
The NPI for Quest Diagnostics LLC is 1780886333, a Type 2 (organization) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-10. Provider record last updated 2007-11-26.