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Dr. Gregory P Williams, DDS

Dr. Gregory P Williams is a Oral and Maxillofacial Surgery (Dentist) provider (Dentist) practicing in Rapid City, SD, registered in the NPPES registry with NPI 1720126220 since 2007. The credential DDS stands for Doctor of Dental Surgery.

✓ Active NPI ✓ Valid NPI checksum Sole proprietor

NPI 1720126220
Entity type Individual (Type 1)
Name Dr. Gregory P Williams
Credential DDS
Sex Male
Practice address Rapid City, SD, 57701
Phone 6053483400
Fax 6053481626
Enumeration date 2007-02-05
Last updated in NPPES 2016-06-28

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

Taxonomy & licenses

Taxonomy code Specialty Primary License State
1223S0112X Oral and Maxillofacial Surgery (Dentist) Primary M808 SD

DDS — Doctor of Dental Surgery: A licensed dentist; DDS and DMD are equivalent dental degrees. About the DDS credential

Other identifiers

Identifier Type State Issuer
8000390 Medicaid SD
Copy-ready billing details
Provider: Gregory Williams, DDS
NPI: 1720126220
Taxonomy: 1223S0112X (Oral and Maxillofacial Surgery (Dentist))
Address: Rapid City, SD, 57701

Other providers at this practice address

NPI Name Type Specialty Location
1659543973 Williams Oral and Maxillofacial Surgery Organization Oral and Maxillofacial Surgery Clinic/Center Rapid City, SD
1407091424 Williams Oral and Maxillofacial Surgery, Prof. L.L.C. Organization Oral and Maxillofacial Surgery (Dentist) Rapid City, SD
1982384483 Rapid City Oral Surgery Prof LLC Organization Oral & Maxillofacial Surgery (D.M.D.) Rapid City, SD

Verify this record

Cross-check NPI 1720126220 against the authoritative CMS record: view Dr. Gregory P Williams 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

How do I verify Gregory Williams's NPI record?
Cross-check NPI 1720126220 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1720126220 active?
Yes — as of the latest NPPES snapshot, NPI 1720126220 is active (record last updated 2016-06-28).

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2016-06-28.