Pre-debut and formation through Stars Awakening Before appearing on the program, several members had already been active in the entertainment industry. In 2018, Doha competed in the survival reality show
Under Nineteen. Junhyeok is a member of the boy group Withus. In 2019, Robin competed in the survival reality show
World Klass. However, he didn't make it into the final lineup. In 2020, Robin and Hanjun competed in the survival reality show
Cap-Teen. They didn't made it to the cut. In 2021, Huiwon competed in the survival reality show
Loud. He didn't made it to the first round. On January 2, 2023, N.SSign released a special single album titled
Woo Woo, containing the lead track of the same name and the track "Have All Except You". On April 18, the group released a pre-debut EP titled
Salty, along with the lead track of the same name. A reissue of the EP titled
Monologue was released on May 27, along with the lead track of the same name.
2023–present: Debut with Birth of Cosmo, Happy & and Tiger On August 9, 2023, N.SSign debuted with the EP
Birth of Cosmo, along with its lead track "Wormhole". A pre-release single "Higher" was released nine days prior on July 31. On October 9, member Doha was announced to be on temporary hiatus for health reasons. The group held their first Japanese concert titled
Birth of Cosmo on November 11 and 12 at
Ariake Arena in
Tokyo, which also marks member Doha's return to the group. On November 29, the group released their first Japanese single "New Star", which also features the Japanese version of "Wormhole" and "Higher". On February 15, 2024, N.SSign released their second EP
Happy &, along with its three title tracks "Happy &", "Funk Jam", and "Love, Love, Love Love Love!". On June 24, member Eddie was announced to be on hiatus. A reissue of
Happy &, titled
Tiger, was released on July 18, 2024, along with the title track of the same name. On August 5, member Hyun was announced to have departed from the group. On December 8, n.CH Entertainment announced that Eddie and Junhyeok have left the group and their contract with the agency was terminated. On December 30, N.SSign released their third EP
Love Potion. ==Members==