The X12 is a series of two-car electric multiple units operated by Statens Järnvägar (SJ) of Sweden as local trains. Eighteen units were built by Asea Brown Boveri in 1991-94, based on the somewhat older X10. From the late 1990s until 2003 three units were also used by Upplands Lokaltrafik. Two of the units have been converted to the successor X14.