Line U3 is a line on the Vienna U-Bahn metro system. Opened in 1991, it currently has 21 stations and a total length of , from to , making it the shortest line on the network. It is connected to at , at , at and at .
It is also currently the only Vienna U-Bahn Line not to be connected with the Badner Bahn.
Line U3 currently serves the following stations: