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Dr. William Vance Esler, MD

Hematology & Oncology Physician in Amarillo, TX · enumerated 2006.

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

National Provider Identifier

1366403685

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Registry record

Entity type Individual (Type 1)
Name Dr. William Vance Esler
Credential MD
Sex Male
Practice address 1000 S Coulter St, Suite 100, Amarillo, TX, 79106
Phone (806) 358-8654
Fax (806) 356-8687
Enumeration date Mar 28, 2006
Last updated in NPPES Feb 18, 2008

Taxonomy & licenses

207RH0003X Hematology & Oncology Physician Allopathic & Osteopathic Physicians · License F1531 (TX) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

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 1366403685 active?
Yes, as of the latest NPPES snapshot, NPI 1366403685 is active (record last updated 2008-02-18).
How do I verify William Esler's NPI record?
Cross-check NPI 1366403685 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 2008-02-18.