Twicecoaster: Lane 1 is the third extended play (EP) by South Korean girl group Twice. The EP was released digitally and physically on October 24, 2016, by JYP Entertainment and distributed by KT Music.

Consisting of seven tracks which features various genres including electropop, dance-pop, deep house, R&B, and rock, the EP is supported by the lead single "TT" produced by Black Eyed Pilseung. It was a commercial success for the group, topping the Gaon Album Chart and surpassing the five-month sales of their previous EP release Page Two in just a week. It then became the highest-selling Korean girl group album on Gaon for the year 2016, selling over 350,000 copies. A Christmas edition of the album was also released on December 19, 2016.

The reissue of the EP, titled Twicecoaster: Lane 2, was released on February 20, 2017.