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Mark J. Tatara, MD

Internal Medicine Physician in Downers Grove, IL · enumerated 2006.

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

National Provider Identifier

1043256324

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Registry record

Entity type Individual (Type 1)
Name Mark J. Tatara
Credential MD
Sex Male
Practice address 6840 Main St Ste 200, Downers Grove, IL, 60516
Phone (630) 869-5382
Fax (630) 869-5383
Enumeration date Jun 22, 2006
Last updated in NPPES Dec 23, 2021

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 036-077438 (IL) 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
0795794 Medicaid OH -
100355690 Medicaid IN -

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

What is the NPI number for Mark Tatara?
The National Provider Identifier (NPI) for Mark Tatara is 1043256324, a Type 1 (individual) record in the CMS NPPES registry.
Where does Mark Tatara practice?
The practice location on file with NPPES is in Downers Grove, IL. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2021-12-23.