Organizers
- See Jane Run
- SEED/The Foundation for Tigard Tualatin Schools
- SEEDS
- SEEDS Classic Rock 5K
- SEEK Ministries Inc.
- Seekers Wild
- Seffner Christian Academy
- Seguin Independent School District
- Seir Kierans NS
- Seits Incorporated
- Select University
- Self Help Center Inc.
- Selkirk Dolphins
- Sell Tennis Camps
- Selsdon Half Marathon
- Semaj 513 Basketball Camp
- Semiahmoo House Society
- Seminole Chamber of Commerce
- Seminole County Parks & Recreation
- Seminole County Parks and Recreation
- Seminole Sports
- SEMO Pumpkin Run
- SEMO Sports Productions
- SEMOY VTT CLUB
- Semper Fit Grand Prix Series
- Semurana Tennis
- SEND International
- Send Town Bike Club
- Seneca Falls Community Little League
- Seneca Janes
- Seneca Sailing Academy, Inc.
- Seni Nursing Assistant Training, LLC
- Senior Coastsiders
- Senior Resource Services
- Sensation Group
- Sense 5K
- SentryWorld
- SEP Tahoe
- SEP Youth Wrestling
- Sepsis Alliance
- Sequim Little League
- Sequoia Brigade Camp
- Sequoia Visalia Kiwanis
- Serenbe
- SereneStrength
- Serenity House Women's Shelter
- Serenoa Golf Club
- Sergio's Soccer Training LLC
- Serious About Fitness
- Serious Cycling
