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Dr. Bret A. Witter, M.D.

Cardiovascular Disease Physician in Los Alamitos, CA · enumerated 2006.

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

National Provider Identifier

1396783387

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Registry record

Entity type Individual (Type 1)
Name Dr. Bret A. Witter
Credential M.D.
Sex Male
Practice address 5300 Katella Ave, Los Alamitos, CA, 90720
Phone (562) 430-7533
Fax (562) 430-8055
Enumeration date Jun 3, 2006
Last updated in NPPES Oct 11, 2018

Taxonomy & licenses

207RC0000X Cardiovascular Disease Physician Allopathic & Osteopathic Physicians · License A45250 (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
00A452500 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.

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Frequently asked questions

Where does Bret Witter practice?
The practice location on file with NPPES is in Los Alamitos, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Bret Witter?
The National Provider Identifier (NPI) for Bret Witter is 1396783387, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2018-10-11.