Organizers
- Texas Team Junior Golf @ Pebble Creek
- Texas Tennis Coaches Association (TTCA)
- Texas Thunder Track Club
- Texas Tornado Boot Camp
- Texas Wild Bunch
- Texins Fitness Center
- Textile Arts Center
- TFA
- TFA I.E. East
- TGA of Arapahoe County
- TGA of Bergen County
- TGA of West Wake County
- TGA Premier Youth Tennis of Douglas County
- TGA Premier Youth Tennis of Plymouth County
- TGA Tucson
- Thalian Association
- Thames Turbo Triathlon Club
- Thank Dank Memorial Scholarship 5K
- Thanks4Giving Race
- Thanksgiving Day Run
- Thanksgiving Point Institute
- Thayer County Running Company
- The Orchard School's Summer Camp
- The "Badge of Honor" Benefit Run
- The 5K Company
- The Academy at Plantation Preserve
- The ACE Project
- The Actor Factory
- The Adirondack Runners
- The Adventure Bureau, LLC
- The After Sunday Project Inc.
- The Angel Fund for ALS Research
- The Animal Care Society
- The Arc Nature Coast
- The Arc Northern Chesapeake Region
- The Arc of Buncombe County
- The Arc of Jefferson County
- The Arc of Tri-Cities
- The Arc of York County
- The Arena Club
- The Army Marathon
- The Art Association of Jackson Hole
- The Art Center Highland Park
- The Art Engine, Inc
- The Art Farm in The City
- The Art Farm NYC
- The Art Garage
- The Art of Life
- The Art Park
- The Art Scene @ CNY Arts Center Inc
