Ernesto J. Villegas, M.D.
Internal Medicine Physician · Chicago, IL
Ernesto J. Villegas, M.D. is an internal medicine physician with a practice address in Chicago, Illinois, and NPI 1871634774, issued on Feb 12, 2007. Check the license on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- Ernesto J. Villegas
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- Practice location
- 311 N Aberdeen St, Chicago, IL 60607
- Phone
- (312) 733-0909
- Enumerated
- Feb 12, 2007
- Record last updated
- Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
- Fax
- (312) 733-0908
- Medicare enrollment
- Enrolled (PECOS I20140307001086); accepts Medicare assignment
- Medical or professional school
- Stanford University School Of Medicine, 1985
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 7,238 in Illinois → Look up another NPI →
Also registered at 311 N Aberdeen St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Rajesh Chattergoon, APNNurse Practitioner1639337942
Verify Ernesto J. Villegas in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersIllinois Department of Financial and Professional RegulationCheck the board
- 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
66% fewer Medicare Part D claims than the average internal medicine physician in 2024
1,068 Medicare Part D claims for 107 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims. 27 claims were for opioids.
Most prescribed
- Atorvastatin Calcium135 claims
- Metformin Hcl86 claims
- Losartan Potassium67 claims
- Amlodipine Besylate56 claims
- Lisinopril45 claims
- Metoprolol Succinate37 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.
Industry payments in 2024: $158.40
1 payment: food and beverage; the largest payer was Davol Inc. The 50,334 providers of this specialty with any payment received $1,303.06 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 one group practice
- Rush University Medical GroupChicago, IL
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Ernesto J. Villegas among 7,238 internal medicine physician records in Illinois
Ernesto J. Villegas, M.D. is one of 7,238 internal medicine physician records with a practice address in Illinois. 73% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2007, is newer than 39% of them.
- NPI issued2007 · 39% of these records are older, 55% newer
- In a Medicare fileYes · 73% of these records are
- In the CMS Doctors and Clinicians fileYes · 50% of these records are
- Graduated1985 · median 2003 among the 3,580 with a school on file
- Record last updated2007 · 47% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
2,867 internal medicine physician records list a practice address in Chicago
They are 2,867 of the 63,379 NPPES records with a practice address in Chicago, and 7,238 internal medicine physician records in Illinois.
All 7,238 in Illinois → Every provider in Chicago → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Jeffrey Dugas, MDChicago, IL 606071760566954
- Joseph Hennessy, M.D.Chicago, IL 606071265407209
- Geralynn Kahn, MD,MPHChicago, IL 606071255320826
- Yosef KazintetChicago, IL 606071538999677
- Elias KhazoumChicago, IL 606071326667304
- Dennis Levinson, M.D.Chicago, IL 606071720050016
- Lin Lin, M.D.Chicago, IL 606071063640217
- Harry Saag, MDChicago, IL 606071295096360
Common questions
What is Ernesto J. Villegas, M.D.'s NPI number?
Ernesto J. Villegas, M.D.'s National Provider Identifier (NPI) is 1871634774, issued on Feb 12, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Ernesto J. Villegas, M.D. located?
The NPPES record lists a practice address at 311 N Aberdeen St, Chicago, IL, 60607. Phone: (312) 733-0909. Providers update this record themselves, so call before visiting.
How can I verify Ernesto J. Villegas, M.D.'s license?
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 Ernesto J. Villegas, M.D. prescribe under Medicare Part D?
In 2024, Ernesto J. Villegas, M.D. had 1,068 Medicare Part D claims for 107 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions 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. 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.