Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

William G Imlach, DO

Individual provider Family Medicine Physician · NPI 1699850610

William G Imlach, DO is registered under Family Practice in Olympia Fields, Illinois. Graduated from Midwestern University, Chicago College of Osteopathic Med in 1993, 33 years ago. Practices with Advocate Health and Hospitals Corporation, a 3,079-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Illinois.

Years since qualifying
33
Trained at
Midwestern University, Chicago College of Osteopathic Med
Licensed in
IL
In the registry since
2006
What do these letters mean?
DO — Doctor of Osteopathic Medicine
A fully licensed physician, trained like an MD with additional musculoskeletal training. Equivalent practice rights in all 50 states.

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Practice location Address checks out

4001 Vollmer Rd
Olympia Fields, IL 60461-1073
Phone: (708) 481-8883
Fax: (708) 481-2917
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Family Medicine Physician (primary) Taxonomy 207Q00000X · Licence 036091396 (IL)

Record details

NPI number1699850610
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorNo
NPI enumeratedOctober 26, 2006
Last updated in NPPESMarch 5, 2025
Certification dateMarch 5, 2025

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyFAMILY PRACTICE
Medical schoolMIDWESTERN UNIVERSITY, CHICAGO COLLEGE OF OSTEOPATHIC MED
Graduated 1993 (33 years in practice)
Group practice Advocate Health And Hospitals Corporation — 3079 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Removal of skin lesions 1–10 times
Removal or shaving of skin growth 1–10 times

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients397
Services billed 26,534 a service is one billed item, such as a visit, a test or a procedure
Average patient age72

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $1,270 71 payments · a meal or drink at a meeting or visit, not a fee
Education $45 1 payment · educational material or training, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician. Those with a page here are linked.

  • Advocate Christ Hospital & Medical Center Hospital · Oak Lawn, IL · listed as Advocate Christ Medical Center
  • Franciscan Health Olympia & Chicago Heights Hospital · Olympia Fields, IL · listed as Franciscan Health Olympia Fields & Chicago Heights
  • Ingalls Memorial Hospital Hospital · Harvey, IL
  • Advocate Trinity Hospital Hospital · Chicago, IL
  • Accentcare Home Health Of Illinois Home health agency · Lombard, IL
  • Advocate Home Health Care Serv Home health agency · Oakbrook, IL
  • Franciscan Home Care Home health agency · Olympia Fields, IL

Colleagues at Advocate Health and Hospitals Corporation

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 3079 clinicians in the practice; 12 are shown here.

Other providers in Olympia Fields