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William G Stone, MD

William G Stone is a Surgery Physician provider (Surgery) practicing in Sonora, CA, registered in the NPPES registry with NPI 1255505764 since 2008. The credential MD stands for Doctor of Medicine.

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NPI 1255505764
Entity type Individual (Type 1)
Name William G Stone
Credential MD
Sex Male
Practice address 900 GREENLEY RD, Sonora, CA, 95370
Phone 6055933688
Enumeration date 2008-04-15
Last updated in NPPES 2022-04-30

Taxonomy & licenses

Taxonomy code Specialty Primary License State
208600000X Surgery Physician Secondary 8495 SD
208600000X Surgery Physician Primary C167208 CA

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: William Stone, MD
NPI: 1255505764
Taxonomy: 208600000X (Surgery Physician)
Address: 900 GREENLEY RD, Sonora, CA, 95370

Other providers at this practice address

NPI Name Type Specialty Location
1336131523 Christi Petersen Individual Nurse Practitioner Sonora, CA
1003807066 Sonora Community Hospital Organization Cardiovascular Disease Physician Sonora, CA
1437135670 James Mosson Individual Internal Medicine Physician Sonora, CA
1013988955 Edman Fuentes Individual Surgical Physician Assistant Sonora, CA
1174583918 Joanne Rios Individual Clinical Nurse Specialist Sonora, CA
1316993405 Oncology Group Inc. Organization Radiation Oncology Physician Sonora, CA
1144268392 James Comazzi Individual Specialist Sonora, CA
1215976576 Shalom Margolis Individual Specialist Sonora, CA

Verify this record

Cross-check NPI 1255505764 against the authoritative CMS record: view William G Stone 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 William Stone?
William Stone is registered in NPPES with the primary taxonomy of Surgery 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 2022-04-30.