| Abbreviation | Definition |
|---|---|
| SNUS | Swaziland National Union of Students |
| SNUS | Swaziland National Unions of Students |
| SOM | Sponsoring, Organizing, Mentoring |
| SOTU | State Of The Union |
| SOUL | Save Our Union License |
| SPCU | Savannah Postal Credit Union |
| SPCU | Sierra Point Credit Union |
| SPDU | Ship Painters and Dockers Union |
| SPEA | Society of Professional Engineers and Associates |
| SPEU | Steel Plant Employees Union |
| SPGU | Sussex Professional Golfers Union |
| SPSU | Singapore Polytechnic Student Union |
| SPSU | Singapore Polytechnic Students Union |
| SPTU | Scandinavian Pet Trade Union |
| SPTU | Somali Public Trade Union |
| SPTU | South Pasadena Tenants Union |
| SPUD | Saint Paul Union Depot |
| SRCU | Sabattus Regional Credit Union |
| SRCU | Shared Resources Credit Union |
| SRCU | Syrian Revolution Coordinators Union |