Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. William G Harris, MD

Allergy & Immunology Physician in Orange, CA · enumerated 2006 · practices at Allergy Partners of California, Inc..

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1922065788

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Registry record

Entity type Individual (Type 1)

Name Dr. William G Harris

Credential MD

Sex Male

Practice address 1140 W La Veta Ave Ste 850, Orange, CA, 92868

Phone (714) 771-7994

Fax (714) 744-4167

Enumeration date Apr 27, 2006

Last updated in NPPES Dec 14, 2023

Taxonomy & licenses

207K00000X Allergy & Immunology Physician Allopathic & Osteopathic Physicians · License G64493 (CA) Primary

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
CB221252	Other	CA	MEDICARE PTAN
00G64493	Medicaid	CA	-

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 → Validate an NPI →

Frequently asked questions

What specialty is William Harris?

William Harris is registered in NPPES with the primary taxonomy of Allergy & Immunology 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.

Other providers at this practice address

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Douglas Brownell Vascular Surgery Physician · Orange, CA NPI 1013020411 Chao-I Lin Allergy & Immunology Physician · Orange, CA NPI 1588779631 Tiffany Wu Surgery Physician · Orange, CA NPI 1629353933 Allergy Partners of California, Inc. Allergy & Immunology Physician · Orange, CA NPI 1144659491 Meena Archie Vascular Surgery Physician · Orange, CA NPI 1588083646 Yela Jung Allergy & Immunology Physician · Orange, CA NPI 1780145573

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2023-12-14.