Leon J. Kosek, O.D.
Optometrist · Frankfort, IL
Leon J. Kosek, O.D. is an optometrist with a practice address in Frankfort, Illinois, and NPI 1801834080, issued on Jun 2, 2006. Check the license (Illinois 046007472, as entered in NPPES) with the Illinois board that licenses this profession; the federal record below is the public data PlainDoctor holds for this provider.
- Name
- Leon J. Kosek
- Credential
- O.D.
- Primary taxonomy
- Optometrist 152W00000X
- License numbers
- 046007472 IL
18001974A IN
Self-reported in NPPES; status is on the state search - Practice location
- 21237 S Lagrange RD, Frankfort, IL 60423
- Phone
- (815) 469-8541
- Enumerated
- Jun 2, 2006
- Record last updated
- Jul 6, 2011 (not updated in 15 years: call before relying on the address or phone)
- Fax
- (815) 469-8126
- Medicaid ID
- 100086900A IN
- Entity
- Type 1 · individual
8 nearest optometrist records → All 2,697 in Illinois → Look up another NPI →
Also registered at 21237 S Lagrange RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Judith Walsh, O.D.Optometrist1548368632
Verify Leon J. Kosek in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich Illinois board licenses this profession
Search for license 046007472Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Leon J. Kosek among 2,697 optometrist records in Illinois
Leon J. Kosek, O.D. is one of 2,697 optometrist records with a practice address in Illinois. 71% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does not. Its NPI, issued in 2006, is newer than 8% of them.
- NPI issued2006 · 8% of these records are older, 63% newer
- In a Medicare fileNo · 71% of these records are
- In the CMS Doctors and Clinicians fileNo · 56% of these records are
- Record last updated2011 · 68% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 152W00000X and a Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
7 optometrist records list a practice address in Frankfort
They are 7 of the 669 NPPES records with a practice address in Frankfort, and 2,697 optometrist records in Illinois. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.
All 2,697 in Illinois → Every provider in Frankfort → Optometrist nationwide →
The 8 optometrist records with the nearest ZIP codes
- Julie Becker, O.DFrankfort, IL 604231679820831
- Kenneth DonauskyFrankfort, IL 604231588732440
- Jena Gilbertson, ODFrankfort, IL 604231225773039
- Steven Guzik, O.D.Frankfort, IL 604231477664035
- Ronald Harrison, O.D.Frankfort, IL 604231205962693
- Judith Walsh, O.D.Frankfort, IL 604231548368632
- Elizabeth Hanno, O.D.Flossmoor, IL 604221750397337
- Wendy Schweinfurth, O.D.Flossmoor, IL 604221396944476
Common questions
What is Leon J. Kosek, O.D.'s NPI number?
Leon J. Kosek, O.D.'s National Provider Identifier (NPI) is 1801834080, issued on Jun 2, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Leon J. Kosek, O.D. located?
The NPPES record lists a practice address at 21237 S Lagrange RD, Frankfort, IL, 60423. Phone: (815) 469-8541. Providers update this record themselves, so call before visiting.
How can I verify Leon J. Kosek, O.D.'s license?
NPPES lists Illinois license number 046007472, as entered by the provider. Search the Illinois board that licenses this profession; the NPPES record confirms identity only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.