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William R Alex, MD

William R Alex is a Surgery Physician provider (Surgery) practicing in Riverside, CA, registered in the NPPES registry with NPI 1558300681 since 2006. The credential MD stands for Doctor of Medicine.

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NPI 1558300681
Entity type Individual (Type 1)
Name William R Alex
Credential MD
Sex Male
Practice address 4000 14TH ST, STE 306, Riverside, CA, 92501
Phone 9516822036
Fax 9516822942
Enumeration date 2006-06-05
Last updated in NPPES 2010-03-19

Taxonomy & licenses

Taxonomy code Specialty Primary License State
208600000X Surgery Physician Primary G86010 CA
2086S0102X Surgical Critical Care Physician Secondary G86010 CA
2086S0127X Trauma Surgery Physician Secondary G86010 CA
208G00000X Thoracic Surgery (Cardiothoracic Vascular Surgery) Physician Secondary G86010 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
00G860100 Medicaid CA
Copy-ready billing details
Provider: William Alex, MD
NPI: 1558300681
Taxonomy: 208600000X (Surgery Physician)
Address: 4000 14TH ST, STE 306, Riverside, CA, 92501

Other providers at this practice address

NPI Name Type Specialty Location
1184620411 James Bartley Individual Clinical Genetics (M.D.) Physician Riverside, CA
1154327773 Ashley Medical Group, Inc Organization Internal Medicine Physician Riverside, CA
1316948110 Norman Snyder Individual Diagnostic Radiology Physician Riverside, CA
1104818459 Riverside Imaging LLC Organization Radiology Clinic/Center Riverside, CA
1164410494 Southern California Transplantation Institute Organization Specialist Riverside, CA
1326014986 Trinh Tang Individual Internal Medicine Physician Riverside, CA
1386687754 Donald Blackman Individual Internal Medicine Physician Riverside, CA
1184735953 William R Alex MD Inc Organization Surgery Physician Riverside, CA

Verify this record

Cross-check NPI 1558300681 against the authoritative CMS record: view William R Alex 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 William Alex practice?
The practice location on file with NPPES is in Riverside, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for William Alex?
The National Provider Identifier (NPI) for William Alex is 1558300681, a Type 1 (individual) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2010-03-19.