The Missouri–Kansas–Texas Railway (reporting mark MKT) is a former Class I railroad company in the United States, with its last headquarters in Dallas. Established in 1865 under the name Union Pacific Railway, Southern Branch, it came to serve an extensive rail network in Texas, Oklahoma, Kansas, and Missouri. In 1988, it merged with the Missouri Pacific Railroad; today, it is part of Union Pacific Railroad.
In the 1890s the MKT was commonly referred to as "the K-T", because for a time it was the Kansas-Texas division of the Missouri Pacific Railroad and "KT" was its abbreviation in timetables as well as its stock exchange symbol. This soon evolved into the nickname "the Katy".