William Zimmermann, M.D.
NPI 1356351845 · Anesthesiology Physician · Rockford, IL
Enrolled with Medicare as Practitioner - Anesthesiology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Zimmermann, M.D. is a Anesthesiology Physician provider in Rockford, IL (NPI 1356351845).
Provider details
- NPI number
- 1356351845
- Entity type
- Individual
- Primary specialty
- Anesthesiology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 036089011 (IL)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)28% of score
52 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Anesthesia for Other Procedure on Large Bowel Using an Endoscope00811 | 14 | $127 |
| Anesthesia for Other Procedure on Esophagus, Stomach, Or Upper Small Bowel Using an Endoscope00731 | 13 | $142 |
| Anesthesia for Procedure on Small and Large Bowel Using an Endoscope00813 | 13 | $162 |
| Anesthesia for X-Ray Or Radiation Therapy01922 | 12 | $208 |
Typical Medicare-allowed amounts for these services range $127–$208 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
Practice location
Mailing address
Additional practice locations (1)
- 12935 Gregory StBlue Island, IL 60406-2428Phone: (708) 824-4494
Registry dates
- Enumerated
- 2006-08-08
- Last updated
- 2025-04-08
- Certified
- 2025-04-08
Frequently asked questions
- What is William Zimmermann's NPI number?
- William Zimmermann's National Provider Identifier (NPI) is 1356351845, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Zimmermann's specialty?
- William Zimmermann is listed in the NPPES registry with a primary specialty of Anesthesiology Physician (Allopathic & Osteopathic Physicians).
- Where is William Zimmermann located?
- William Zimmermann's practice location on file with NPPES is 8201 E Riverside Blvd, Rockford, IL 61114-2300.
- What is William Zimmermann's phone number?
- The practice phone number listed in the NPPES registry for William Zimmermann is (815) 971-7000.
- Does William Zimmermann accept Medicare?
- William Zimmermann is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Zimmermann's NPI active?
- Yes — William Zimmermann's NPI (1356351845) is active in the NPPES registry as of the last update on 2025-04-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.