- A to Z Vending Services, Inc.
- AC Nielsen
- Academy of Financial Services Studies, LLC
- Adjustable Fixture Company
- Aegis
- Affinity Health System
- Agnesian Healthcare - St. Agnes Hospital
- Alliant Energy
- American Computer Software, LLC
- American Data
- American Family Insurance Group
- American Lung Association in Wisconsin
- Apollo Corporation
- Ascension All Saints Hospital
- Ascension Calumet Medical Center
- Ascension Columbia St. Mary's Hospital Milwaukee
- Ascension Columbia St. Mary's Ozaukee Hospital
- Ascension Elmbrook Memorial Hospital
- Ascension Franklin Hospital
- Ascension NE Wisconsin - Mercy Campus
- Ascension Sacred Heart Hospital-St. Mary's Hospital
- Ascension SE Wisconsin Hospital - St. Joseph Campus
- Ascension SE Wisconsin Hospital- St. Joseph Campus
- Ascension St. Clare's Hospital
- Ascension St. Elizabeth Hospital
- Ascension St. Francis Hospital
- Aspirus Eagle River
- Aspirus Howard Young Medical Center
- Aspirus Tomahawk and Aspirus Rhinelander
- Aspirus Wausau Hospital
- Association Builders and Contractors of Wisconsin Inc
- ATSF - American Tissue Services Foundation
- Aurora BayCare Medical Center
- Aurora Health Care
- Aurora Lakeland Medical Center
- Aurora Medical Center in Burlington
- Aurora Medical Center in Grafton
- Aurora Medical Center in Kenosha
- Aurora Medical Center in Manitowoc County
- Aurora Medical Center in Oshkosh
- Aurora Medical Center in Summit
- Aurora Medical Center in Washington County
- Aurora Sheboygan Memorial Medical Center
- Aurora Sinai Medical Center
- Aurora St. Luke's Medical Center
- Aurora St. Luke's Medical Center South Shore
- Aurora West Allis Medical Center
- Badger Meter
- Banta Corporation
- Bayfield County