USS
- Star Trek
- Swiss Trade Union Confederation
- U.S. Steel
- UNIX System Services
- USA Swimming
- Ubiquitous Synergy Seeker
- Union of Sovereign States
- United Peasant Party
- United Seamen's Service
- United State of Saurashtra
- United States Senate
- United States Ship
- United States Standard
- Universal Studios Singapore
- Universities Superannuation Scheme
- University of Southern Somalia
- Upshaw–Schulman syndrome
- Uxbridge Secondary School
- VTAM