Tachileik is a border town located in the Shan State of eastern Myanmar. It serves as the administrative seat for both Tachileik Township and Tachileik District.
As the most populated city in eastern Shan State, Tachileik had a population of 51,553 according to the 2014 census count. The town faces Mae Sai in Thailand and hosts one of Myanmar's seven official border trade posts with its neighbor.