Spencer Chamberlain is an American musician, best known for being the current lead vocalist for the rock band Underoath. Before fronting Underoath, Chamberlain was the vocalist for the band This Runs Through in which his brother, Phil Chamberlain, was the drummer.

Underoath is an American rock band from Tampa, Florida. It was founded by lead vocalist Dallas Taylor and guitarist Luke Morton in 1997 in Ocala, Florida; subsequently, its additional members were from Tampa, including drummer, clean vocalist and last remaining core member Aaron Gillespie. The band's current lineup consists of Gillespie, keyboardist Christopher Dudley, lead guitarist Timothy McTague, bassist Grant Brandell, and lead vocalist Spencer Chamberlain. Originally, the band identified as a Christian group; they have since distanced themselves from Christianity.