costee

Jussi Tiainen (born January 12, 1995), known professionally as costee (stylized entirely in lower-case), is a Finnish singer-songwriter. Originally a member of the Turku-based duo Sima, he began his own solo career in 2018. He participated in Uuden Musiikin Kilpailu 2025, where he ultimately placed sixth. He has been nominated for two Emma Awards.