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Ratnam A Oza, MD

Internal Medicine Physician in Dayton, OH · enumerated 2005.

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

National Provider Identifier

1003816687

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Registry record

Entity type Individual (Type 1)
Name Ratnam A Oza
Credential MD
Sex Male
Practice address 1100 S Main St, Ste. 203, Dayton, OH, 45409
Phone (937) 222-0603
Fax (937) 222-7122
Enumeration date Jul 26, 2005
Last updated in NPPES Feb 16, 2011

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 35044276 (OH) Primary
207RG0300X Geriatric Medicine (Internal Medicine) Physician Allopathic & Osteopathic Physicians · License 35044276 (OH) Secondary
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
000000281449 Other OH ANTHEM
0498304 Medicaid OH -

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 Ratnam Oza practice?
The practice location on file with NPPES is in Dayton, OH. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Ratnam Oza?
The National Provider Identifier (NPI) for Ratnam Oza is 1003816687, 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 2011-02-16.