- U.S. Centers for Disease Control and Prevention (CDC)
- U.S. Department of Housing & Urban Development
- U.S. Environmental Protection Agency
- Uday Apte
- Uday S. Karmarkar
- Uğur Eliiyi
- Uli Chi
- Ulrich Derigs
- Ulrich W. Thonemann
- Umit Deniz Tursun
- Umit G. Gurun
- Umut Mururoglu
- United Airlines
- United Nations World Food Programme
- United States Air Force
- United States Army
- United States Coast Guard
- United States Coast Guard
- United States Coast Guard Academy Student Chapter
- University at Buffalo Student Chapter