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Dr. Sinclair W Armstrong Jr., MD

Dr. Sinclair W Armstrong Jr. is a Urology Physician provider (Urology) practicing in Fort Smith, AR, registered in the NPPES registry with NPI 1861435752 since 2006. The credential MD stands for Doctor of Medicine.

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NPI 1861435752
Entity type Individual (Type 1)
Name Dr. Sinclair W Armstrong Jr.
Credential MD
Sex Male
Practice address 7001 ROGERS AVE, Fort Smith, AR, 72903
Phone 4794522077
Enumeration date 2006-06-14
Last updated in NPPES 2007-07-08

Taxonomy & licenses

Taxonomy code Specialty Primary License State
208800000X Urology Physician Primary R-2359 AR

MD — Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Copy-ready billing details
Provider: Sinclair Armstrong, MD
NPI: 1861435752
Taxonomy: 208800000X (Urology Physician)
Address: 7001 ROGERS AVE, Fort Smith, AR, 72903

Other providers at this practice address

NPI Name Type Specialty Location
1467456954 Andre Nolewajka Individual Interventional Cardiology Physician Fort Smith, AR
1073570156 Stuart Haraway Individual Obstetrics & Gynecology Physician Fort Smith, AR
1013960442 Raymond Goodman Individual Surgery Physician Fort Smith, AR
1396786042 Eastside Ob/Gyn P.L.L.C. Organization Obstetrics & Gynecology Physician Fort Smith, AR
1740224831 Timothy Bell Individual Obstetrics & Gynecology Physician Fort Smith, AR
1568406650 Casey Laws Individual Obstetrics & Gynecology Physician Fort Smith, AR
1073557005 Melissa Rainwater Individual Obstetrics & Gynecology Physician Fort Smith, AR
1962430504 Christopher Coleman Individual Surgery Physician Fort Smith, AR

Verify this record

Cross-check NPI 1861435752 against the authoritative CMS record: view Dr. Sinclair W Armstrong Jr. 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

What specialty is Sinclair Armstrong?
Sinclair Armstrong is registered in NPPES with the primary taxonomy of Urology Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2007-07-08.