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WILLIAM R ZIMMERMANN M.D.
NPI 1356351845
Anesthesiology in Rockford, IL

Active since August 08, 2006PECOS EnrolledAccepts Medicare Assignment
8201 E RIVERSIDE BLVD, ROCKFORD, IL 61114(815) 971-7000 Get Directions Write a Review

NPPES record last updated: April 8, 2025. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About William R Zimmermann M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

WILLIAM R ZIMMERMANN M.D. (NPI 1356351845) is an individual anesthesiology provider in Rockford, Illinois, licensed in Illinois (036089011) and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS, is affiliated with Loyola Gottlieb Memorial Hospital, and maintains a secondary practice location in Blue Island.

NPPES Registry Identity

NPI1356351845
Entity TypeIndividualMale
Primary Taxonomy207L00000X
Provider Legal NameWILLIAM R ZIMMERMANNCredential: M.D.
Location Address8201 E RIVERSIDE BLVDRockford, IL 61114-2300
Mailing Address29624 Network PlChicago, IL 60673-1296 · (608) 756-6278
Phone(815) 971-7000
Sole ProprietorNo
Medical School CMSOtherGraduated 1989
Enumeration DateAugust 8, 2006
Last NPPES UpdateApril 8, 2025
NPPES CertifiedApril 8, 2025
✔ NPI 1356351845 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyAnesthesiologyAllopathic & Osteopathic Physicians
Taxonomy Code207L00000X
License✔ Licensed in IL · 036089011
Definition
An anesthesiologist is trained to provide pain relief and maintenance, or restoration, of a stable condition during and immediately following an operation or an obstetric or diagnostic procedure. The anesthesiologist assesses the risk of the patient undergoing surgery and optimizes the patient's condition prior to, during and after surgery. In addition to these management responsibilities, the anesthesiologist provides medical management and consultation in pain management and critical care medicine. Anesthesiologists diagnose and treat acute, long-standing and cancer pain problems; diagnose and treat patients with critical illnesses or severe injuries; direct resuscitation in the care of patients with cardiac or respiratory emergencies, including the need for artificial ventilation; and supervise post-anesthesia recovery.
8201 E RIVERSIDE BLVD, Rockford, IL 61114
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Secondary Practice Location 1

Location 112935 Gregory StBlue Island, IL 60406-2428 · Phone (708) 824-4494

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

William R Zimmermann M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID2769376607
PECOS Enrollment IDI20040211000504, I20260507000903
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

11

Medicare enrollment records show William Zimmermann reassigns Medicare billing to 11 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Rockford Health Physicians
Same address
Multi-Specialty
8201 E RIVERSIDE BLVD
Rockford, IL 61114
  • Reassigned Medicare billing, Illinois enrollment
  • 1,375 clinicians in this Medicare group
NPI 1043242886 (608) 314-2428
Valley Pain Care Centers Ltd
29 mi
Pain Medicine
1 KISH HOSPITAL DR
Dekalb, IL 60115
  • Reassigned Medicare billing, Illinois enrollment
  • 57 clinicians in this Medicare group
NPI 1194722058 (815) 766-1258
Anesthesia Associates, Ltd
52 mi
Pain Medicine
2540 HANFORD LN
Aurora, IL 60502
  • Reassigned Medicare billing, Illinois enrollment
  • 101 clinicians in this Medicare group
NPI 1952308223 (815) 748-8993
Central Dupage Physician Group
56 mi
Family Medicine
5777 DEPARTMENT
Carol Stream, IL 60122
  • Reassigned Medicare billing, Illinois enrollment
  • 1,664 clinicians in this Medicare group
NPI 1033149844 (630) 933-3300
Hsc Anesthesia Services LLC
64 mi
Anesthesiology
10 SALT CREEK LN
Hinsdale, IL 60521
  • Reassigned Medicare billing, Illinois enrollment
  • 35 clinicians in this Medicare group
NPI 1174239719 (630) 323-5214
Loyola University Medical Center
66 mi
General Practice
2160 S 1ST AVE
Maywood, IL 60153
  • Reassigned Medicare billing, Illinois enrollment
  • 1,138 clinicians in this Medicare group
NPI 1336159961 (708) 216-3215
Windy City Anesthesia PC
80 mi
Nurse Anesthetist, Certified Registered
21120 WASHINGTON PKWY
Frankfort, IL 60423
  • Reassigned Medicare billing, Illinois enrollment
  • 164 clinicians in this Medicare group
NPI 1932248622 (847) 691-9080
Associated Anesthesiologists, S.C.
113 mi
Anesthesiology
6742 N FROSTWOOD PKWY
Peoria, IL 61615
  • Reassigned Medicare billing, Illinois enrollment
  • Medicare enrollment name: Associated Anesthesiologists Sc
  • 337 clinicians in this Medicare group
NPI 1558306480 (309) 692-5393
Auburn Community Hospital
633 mi
General Acute Care Hospital
17 LANSING ST
Auburn, NY 13021
  • Reassigned Medicare billing, New York enrollment
  • 277 clinicians in this Medicare group
NPI 1093712911 (315) 255-7209
Auburn Medical PC
633 mi
Anesthesiology
17 LANSING ST
Auburn, NY 13021
  • Reassigned Medicare billing, New York enrollment
  • 36 clinicians in this Medicare group
NPI 1861590432 (315) 449-0513

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 4

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Anesthesia for other procedure on large bowel using an endoscope 00811
Anesthesia for an endoscopic procedure on the large bowel ensures comfort and relaxation during the procedure. You'll be given medication to make you drowsy or asleep, eliminating any discomfort. The medication can be administered through a vein or inhaled.
14 services14 patients
Anesthesia for other procedure on esophagus, stomach, or upper small bowel using an endoscope 00731
This procedure involves the use of an endoscope, a flexible tube with a light and camera, to examine your esophagus, stomach, or upper small bowel. Anesthesia ensures you are comfortable and pain-free during the procedure.
13 services12 patients
Anesthesia for procedure on small and large bowel using an endoscope 00813
Anesthesia for an endoscopic procedure on the small and large bowel ensures comfort and relaxation during the procedure. It involves administering medicine to help you sleep or feel drowsy. This allows the doctor to examine your bowels without causing you discomfort or pain.
13 services13 patients
Anesthesia for x-ray or radiation therapy 01922
Anesthesia for x-ray or radiation therapy involves administering medication to help you relax or sleep during the procedure. It's used to ensure comfort, minimize movement, and reduce anxiety. The type of anesthesia used depends on the procedure and patient's health.
12 services12 patients

Hospital Affiliations CMS Care Compare 3

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Loyola Gottlieb Memorial Hospital

Acute Care Hospitals · Melrose Park, IL
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number140008
Location701 West North AveMelrose Park, IL 60160 · Cook County
Emergency services

Macneal Hospital

Acute Care Hospitals · Berwyn, IL
2/5 CMS rating
OwnershipProprietary
CMS Certification Number140054
Location3249 South Oak Park AvenueBerwyn, IL 60402 · Cook County
Emergency services Birthing friendly

Auburn Community Hospital

Acute Care Hospitals · Auburn, NY
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number330235
Location17 Lansing StreetAuburn, NY 13021 · Cayuga County
Emergency services Birthing friendly

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. BHARGAV DESAI M.D.
Neurological Surgery
8201 E RIVERSIDE BLVD
ROCKFORD, IL 61114
Winnebago County (815) 971-7000
DR. ALIX VINCENT MD
Radiology (Neuroradiology)
8201 E RIVERSIDE BLVD
ROCKFORD, IL 61114
Winnebago County (815) 971-7000
ERIN MARGARET OZMINKOWSKI
Internal Medicine
8201 E RIVERSIDE BLVD
ROCKFORD, IL 61114
Winnebago County (815) 971-6364
LAURA MADLINGER LEWIS OTD. OTR/L, CNT
Occupational Therapist
8201 E RIVERSIDE BLVD
ROCKFORD, IL 61114
Winnebago County (815) 971-7000
STEPHANIE YEAGER APN
Internal Medicine (Hospice and Palliative Medicine)
8201 E RIVERSIDE BLVD
ROCKFORD, IL 61114
Winnebago County (815) 971-5000
CAMERON JOSEPH SMITH PHARMD
Pharmacist
8201 E RIVERSIDE BLVD
ROCKFORD, IL 61114
Winnebago County (815) 971-7000
KARL E. MAGSAMEN M.D.
Radiology (Vascular & Interventional Radiology)
8201 E RIVERSIDE BLVD
ROCKFORD, IL 61114
Winnebago County (815) 971-7000
CHRISTINE NA-EUN MILLAR MD
Anesthesiology
8201 E RIVERSIDE BLVD
ROCKFORD, IL 61114
Winnebago County (815) 971-7000

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is William Zimmermann's NPI number?

The NPI number for William Zimmermann is 1356351845. It was assigned to this individual provider in the NPPES registry on August 8, 2006.

Where is William Zimmermann located?

William Zimmermann practices at 8201 E Riverside Blvd, Rockford, IL 61114. The listed phone number is (815) 971-7000.

What is William Zimmermann's specialty?

The primary specialty registered for this NPI is Anesthesiology with taxonomy code 207L00000X.

Is William Zimmermann enrolled in Medicare?

Yes. William Zimmermann is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organizations bill Medicare for William Zimmermann's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Zimmermann reassigns Medicare benefits to 11 organizations: Rockford Health Physicians (Rockford, IL), Valley Pain Care Centers Ltd (Dekalb, IL), Anesthesia Associates, Ltd (Aurora, IL), Central Dupage Physician Group (Carol Stream, IL), Hsc Anesthesia Services LLC (Hinsdale, IL) and 6 more organizations, listed in the Medicare section above. Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for William Zimmermann's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is William Zimmermann affiliated with any hospitals?

According to CMS data, William Zimmermann is affiliated with Loyola Gottlieb Memorial Hospital, Macneal Hospital and Auburn Community Hospital.

When was this NPI record last updated?

The NPPES record for William Zimmermann was last updated on April 8, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 18 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.