Composed of the four Girls' Generation members who remained with the agency after the expiration of their contracts: Taeyeon, Hyoyeon, Yuri, and Yoona.

On October 9, 2017, Girls' Generation members Seohyun, Tiffany and Sooyoung decided to leave SM Entertainment, effectively putting the group on hiatus.

The label later announced the group was not disbanded, and future involvement with the three members and Girls' Generation would be discussed.

[2] On August 27, SM Entertainment unveiled Girls' Generation-Oh!GG as the group's second unit, consisting of the members still signed to the label.

[3] The group made its debut on September 5 with the single "Lil' Touch", which was released in both digital and physical formats.