U
- US Automobile (1899–1901)
- Union (1902–1905)
- Union (1908–1909)
- Union (1916)
- United (1914)
- United (1919–1920)
- United States (1899–1903)
- United States Long Distance (see Long Distance)
- Unito (1908–1910)
- Universal (1914)
- Upton (1902–1903)
- Upton (1905–1907)
- U.S. Runabout (1907–1908)
Read more about this topic: List Of Defunct Automobile Manufacturers Of The United States