- Society of Fire Protection Engineers
- Society of Government Meeting Professionals
- Society of Government Travel Professionals
- Society of Independent Gasoline Marketers of America SIGMA)
- Society of Permanent Cosmetic Professionals
- Society of Petroleum Engineers
- Society of Professional Journalists
- Society of Teachers of Family Medicine
- Socius Corporation
- SOD University of Arizona
- Sodexo Quality of Life Services
- SoftEdge Inc.
- Softscape
- Software Management, Inc.
- Software Solutions
- Solano Coalition for Better Health
- Solano County
- Solano County Sheriff's Office
- Solara Hospitals - McAllen and Edinburg
- Solara Specialty Hospitals Harlingen
- Solaris Health System
- Soldiers and Sailors Memorial Hospital
- Solheim Lutheran Home
- Solix, Inc.
- Solutions for Progress
- Solve Cares, Inc
- Somerset Community College
- Somerset County
- Somerset Hospital
- Somerset Medical Center
- Somerset Valley Bank
- Somervell Co. VFD
- Sommers Law Group, LLC
- Song of the Sea, Sanibel Island
- Sonoma County In Home Support Service
- Sonoma Funeral Home
- Sonoma State University
- Sonopress, LLC
- Sony Music, Inc.
- Soroptimist International of Winfield
- Sorrento Lactalis, Inc.
- SOS Staffing Services
- Souderton Mennonite Homes
- Soulwise Enterprises
- Source 1 Staffing of Prevaro
- Source Diversified, Inc.
- Source Staffing
- SourceAmerica
- South Asian Bar Association Foundation
- South Asian Network