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Mark Irwin, M.D.

Internal Medicine Physician in Belleville, IL · enumerated 2005.

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

National Provider Identifier

1366433567

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Registry record

Entity type Individual (Type 1)
Name Mark Irwin
Credential M.D.
Sex Male
Practice address 2900 Frank Scott Pkwy W, Suite 904, Belleville, IL, 62223
Phone (618) 234-0640
Fax (314) 851-4475
Enumeration date Nov 4, 2005
Last updated in NPPES Sep 21, 2012

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 336-023425 (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
036058840 Medicaid IL -
000000010019 Other IL ESSENCE
113626 Other IL HEALTHLINK
8221955 Other IL BCBS IL
127443 Other IL GHP
129537 Other IL BCBS TRI ST
129537 Other IL BCBS
0450347 Other IL UHC
5561291 Other IL AETNA
D14440 Other IL MERCY

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 Mark Irwin practice?
The practice location on file with NPPES is in Belleville, IL. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mark Irwin?
The National Provider Identifier (NPI) for Mark Irwin is 1366433567, 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 2012-09-21.