NPI Portal NPI Lookup & Verification

Gregory John Duncan, M.D.

Gregory John Duncan is a Orthopaedic Surgery Physician provider (Orthopaedic Surgery) practicing in Wrangell, AK, registered in the NPPES registry with NPI 1164459921 since 2006. The credential MD stands for Doctor of Medicine.

✓ Active NPI ✓ Valid NPI checksum Sole proprietor

NPI 1164459921
Entity type Individual (Type 1)
Name Gregory John Duncan
Credential M.D.
Sex Male
Practice address Wrangell, AK, 99929
Phone 7079519203
Enumeration date 2006-06-27
Last updated in NPPES 2023-02-09

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

Taxonomy & licenses

Taxonomy code Specialty Primary License State
207X00000X Orthopaedic Surgery Physician Primary A44032 CA

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

Other identifiers

Identifier Type State Issuer
A044032 Other CA CALIFORNIA MEDICAL LICENSE
P00181543 Other CA RAILROAD MEDICARE
00A440320 Medicaid CA
Copy-ready billing details
Provider: Gregory Duncan, M.D.
NPI: 1164459921
Taxonomy: 207X00000X (Orthopaedic Surgery Physician)
Address: Wrangell, AK, 99929

Verify this record

Cross-check NPI 1164459921 against the authoritative CMS record: view Gregory John Duncan 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

Where does Gregory Duncan practice?
The practice location on file with NPPES is in Wrangell, AK. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Gregory Duncan?
The National Provider Identifier (NPI) for Gregory Duncan is 1164459921, a Type 1 (individual) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2023-02-09.