On April 19, 2012, S.M. Entertainment officially announced the formation of the subgroup, stating in their official press release that the intention was to "grab the attention of fans with all aspects of music, performance, and fashion styles." It also hinted at the possibility of other future subgroups, elaborating, "the members of the unit are rotated according to the unique music and concept of each new subgroup album." The name "TaeTiSeo", or "TTS", is made up of the first syllables of Taeyeon, Tiffany, and Seohyun. Compared to the 8-member Girls' Generation, TTS's main focus is on each member's vocal ability while the original group places more emphasis on the overall songs and uniform group performances.
In 2014, the three singers were featured in the reality show The TaeTiSeo. The show took on the personal side of Taeyeon, Tiffany and Seohyun, revealing how they live their normal everyday lives and what they do in their free time. Some footage of the album preparation was shown.