WILLIAM SAUER MD
NPI 1609827583
Internal Medicine - Clinical Cardiac Electrophysiology in Chicago, IL
About William Sauer Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
WILLIAM SAUER MD (NPI 1609827583) is an individual clinical cardiac electrophysiology provider in Chicago, Illinois, licensed in Illinois (036177896) and active in the NPI registry since May 2006. He is enrolled in Medicare PECOS, is affiliated with The University Of Chicago Medical Center, and is a graduate of Other (1999).
NPPES Registry Identity
Specialties & Licenses 2
Other Identifiers 1
Accepted Insurance
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 Sauer Md 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.
Medicare Billing Reassignments
3Medicare enrollment records show William Sauer reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Chicago, IL 60637
- Reassigned Medicare billing, Illinois enrollment
- 1,905 clinicians in this Medicare group
Chicago, IL 60637
- Reassigned Medicare billing, Illinois enrollment
- Also billed through NPI 1477262046 (Illinois)
- 2,237 clinicians in this Medicare group
Boston, MA 02115
- Reassigned Medicare billing, Massachusetts enrollment
- 4,574 clinicians in this Medicare group
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 26
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.
Hospital Affiliations CMS Care Compare 4
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
The University Of Chicago Medical Center
Acute Care Hospitals · Chicago, ILMassachusetts General Hospital
Acute Care Hospitals · Boston, MABrigham And Women's Hospital
Acute Care Hospitals · Boston, MAFaulkner Hospital-Brigham And Women's
Acute Care Hospitals · Boston, MAPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 60637 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
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.
CHICAGO, IL 60637
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 Sauer's NPI number?
The NPI number for William Sauer is 1609827583. It was assigned to this individual provider in the NPPES registry on May 15, 2006.
Where is William Sauer located?
William Sauer practices at 5841 S Maryland Ave, Chicago, IL 60637. The listed phone number is (888) 824-0200.
What is William Sauer's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Clinical Cardiac Electrophysiology, with taxonomy code 207RC0001X.
Is William Sauer enrolled in Medicare?
Yes. William Sauer 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 Sauer's services?
According to the CMS Revalidation Reassignment List (October 2026 release), William Sauer reassigns Medicare benefits to 3 organizations: The University Of Chicago Medical Center (Chicago, IL), University Of Chicago (Chicago, IL) and Brigham & Womens Physicians Organization Inc (Boston, MA). 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 Sauer's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does William Sauer accept?
Health plans from Taro Health list William Sauer as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.
Is William Sauer affiliated with any hospitals?
According to CMS data, William Sauer is affiliated with The University Of Chicago Medical Center, Massachusetts General Hospital, Brigham And Women's Hospital and Faulkner Hospital-Brigham And Women's.
When was this NPI record last updated?
The NPPES record for William Sauer was last updated on July 21, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.