William H. Kobak, M.D.
Gynecology Physician · St Charles, IL
William H. Kobak, M.D. is a gynecology physician with a practice address in St Charles, Illinois, and NPI 1023007887, issued on Oct 14, 2005. Check the license (Illinois 036091917, as entered in NPPES) on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- William H. Kobak
- Credential
- M.D.
- Primary taxonomy
- Gynecology Physician 207VG0400X
- License number
- 036091917 IL
Self-reported in NPPES; status is on the state search - Practice location
- 3310 W Main St, St Charles, IL 60175
- Phone
- (630) 897-6044
- Enumerated
- Oct 14, 2005
- Record last updated
- Jan 29, 2025
- Fax
- (630) 897-0180
- Medicaid ID
- 036091917 IL
- Medicare enrollment
- Enrolled (PECOS I20041129000048); accepts Medicare assignment
- Medical or professional school
- Indiana University School Of Medicine, 1989
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest gynecology physician records → All 113 in Illinois → Look up another NPI →
Also registered at 3310 W Main St
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Thomas Dovidio, DOPediatrics Physician1316141203
- Leticia Gonzalez, M.D.Obstetrics & Gynecology Physician1356313720
- Kim Harmon, M.D.Obstetrics & Gynecology Physician1932188299
Verify William H. Kobak in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersIllinois Department of Financial and Professional Regulation
Search for license 036091917Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
7% fewer Medicare Part D claims than the average gynecology physician in 2024
279 Medicare Part D claims for 87 beneficiaries, against an average of 299 among the 1,919 providers of this specialty who prescribed in Part D. Brand-name drugs were 22% of claims.
Most prescribed
- Estradiol96 claims
- Myrbetriq43 claims
- Methenamine Hippurate25 claims
- Solifenacin Succinate19 claims
- Trospium Chloride19 claims
- Oxybutynin Chloride Er17 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
The practice group's MIPS final score for 2023 (Medicare payment program): 80.8 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $13.18
1 payment: food and beverage; the largest payer was Boston Scientific Corporation. The 1,398 providers of this specialty with any payment received $2,469.88 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through 2 group practices
- Cook CountyChicago, IL
- The Board OF Trustees OF The University OF IllinoisChicago, IL
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William H. Kobak among 113 gynecology physician records in Illinois
William H. Kobak, M.D. is one of 113 gynecology physician records with a practice address in Illinois. 55% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 83% newer
- In a Medicare fileYes · 55% of these records are
- In the CMS Doctors and Clinicians fileYes · 35% of these records are
- Graduated1989 · median 1998 among the 40 with a school on file
- Record last updated2025 · 65% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207VG0400X and a Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gynecology Physician providers in Illinois
There are 113 gynecology physician records in Illinois.
All 113 in Illinois → Every provider in St Charles → Gynecology Physician nationwide →
The 8 gynecology physician records with the nearest ZIP codes
- Marilyn MitchellSt Charles, IL 601741851380067
- Kenneth Noffsinger, MDSt Charles, IL 601741669485017
- David RobinsonSchaumburg, IL 601731467028738
- Jennifer McCormick, M.D.Sycamore, IL 601781548272685
- John Messitt, M. D.Wheaton, IL 601871255427639
- Ashima Mehta, MDMelrose Park, IL 601601932180130
- Mary Lynn, DOMaywood, IL 601531841379690
- Daphne Moloney, MDEvanston, IL 602011346319167
Common questions
What is William H. Kobak, M.D.'s NPI number?
William H. Kobak, M.D.'s National Provider Identifier (NPI) is 1023007887, issued on Oct 14, 2005. An NPI identifies a provider in billing; it is not a license.
Where is William H. Kobak, M.D. located?
The NPPES record lists a practice address at 3310 W Main St, St Charles, IL, 60175. Phone: (630) 897-6044. Providers update this record themselves, so call before visiting.
How can I verify William H. Kobak, M.D.'s license?
NPPES lists Illinois license number 036091917, as entered by the provider. Search the Illinois Department of Financial and Professional Regulation at https://idfpr.illinois.gov/checklicense.html. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does William H. Kobak, M.D. prescribe under Medicare Part D?
In 2024, William H. Kobak, M.D. had 279 Medicare Part D claims for 87 beneficiaries; the average among gynecology physician prescribers was 299. Part D covers Medicare prescriptions only.
What is William H. Kobak, M.D.'s MIPS final score?
The 2023 MIPS final score is 80.8 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. 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.