On February 17, 2019, the agency revealed that they would debut a new girl group named EVERGLOW. On the same day, they opened the staff and group's Twitter, Instagram, and Fancafe accounts. On the group's social medias, a teaser was posted revealing the official logo of the group. On February 18, an article was published on Naver, revealing that former Produce 48 contestants Kim Sihyeon and Wang Yiren was included in the group's lineup. On the same day, a teaser video was posted on Stone Music Entertainment's channel on YouTube, confirming Sihyeon as the first member. On the following day, the second member, Mia, was revealed with a teaser as well. The third member, Onda, was revealed on February 20, followed by the fourth member Yiren on February 21. On February 24, the fifth member, E:U, was revealed. The sixth and last member, Aisha, was revealed on February 25, 2019.
On March 3, 2019, the concept photos of the group and the members was revealed.