- 7-Eleven, Inc.
- A-Rocket Moving and Storage Inc.
- A2D Technologies
- AandC Plastic Products Inc.
- Abilene Convention and Visitors Bureau
- AccessHealth
- Acres Home Citizens Chamber of Commerce
- Adam's Mark Downtown Dallas
- Addison Visitors Services Dept.
- Adonai Networking and Logistics Solutioins
- Advanced Solutions International
- AdventHealth Central Texas
- Affordable Pet Care P.C.
- AFLAC
- Aguirre Corporation
- Air Force Information Warfare
- Alamo Industrial
- Allograft Resources
- Alta Health Institute
- Alvin Community College
- American Airlines
- American CityVista, LLC
- American College of Emergency Physicians
- American Diabetes Association - Central South Texas Office
- American Fire Sprinkler Association
- American General Corporation-AIG
- American Heart Association
- American Institute of Architects - TX
- American Lighting Association
- American Medical Equipment Company
- American Mensa Ltd.
- American Outcomes Management, LP
- Analytical Computer Services
- Ancira Enterprises Inc.
- Aquila Golf, Inc.
- Aramark
- Archdiocese of San Antonio
- Ascension Providence
- Ascension Providence
- Ascension Seton
- Ascension Seton Hays
- Ascension Seton Heart Specialty Care and Transplant Center
- Ascension Seton Medical Center Austin
- Ascension Seton Northwest
- Ascension Seton Williamson
- Associated Locksmiths of America
- Associated Plumbing Heating Cooling Contractors of Texas
- Association for Student Judicial Affairs
- ATandT
- ATP Oil and Gas Corporation