Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Mr. Thomas O'Callaghan, MD

Surgery Physician in Loma Linda, CA · enumerated 2005.

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

National Provider Identifier

1699751321

Verified

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Registry record

Entity type Individual (Type 1)

Name Mr. Thomas O'Callaghan

Credential MD

Sex Male

Practice address 11370 Anderson St, Ste. 2100, Loma Linda, CA, 92354

Phone (909) 558-2822

Enumeration date Dec 15, 2005

Last updated in NPPES Oct 4, 2007

Taxonomy & licenses

208600000X Surgery Physician Allopathic & Osteopathic Physicians · License C42550 (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
00C425500	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

Where does Thomas O'Callaghan practice?

The practice location on file with NPPES is in Loma Linda, CA. Providers can have multiple locations; NPPES lists the primary practice address.

What is the NPI number for Thomas O'Callaghan?

The National Provider Identifier (NPI) for Thomas O'Callaghan is 1699751321, a Type 1 (individual) record in the CMS NPPES registry.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-10-04.