Styx formed in Chicago. Twin brothers Chuck and John Panozzo first got together with their neighbor Dennis DeYoung in 1961 in the Roseland section of the south side of Chicago, eventually taking the band name "The Tradewinds". Chuck Panozzo left to attend seminary school for a year but returned to the group by 1964. By this time, the others had brought in guitarist Tom Nardini to teach Chuck the guitar. Chuck decided to rejoin the others as bassist. Brother John was the drummer, while Dennis had switched from accordion to organ and piano. In 1965, the name "Tradewinds" was changed to TW4 after another band called The Trade Winds broke through nationally. By 1966, the Panozzo brothers had joined DeYoung at Chicago State University and kept the group together doing gigs at high schools and frat parties while studying to be teachers. In 1969, they added a college buddy, John Curulewski, on guitar after Nardini departed. Guitarist James "J.Y." Young came aboard in 1970 making TW4 a quintet.
In 1972, the band members decided to choose a new name when they signed to Wooden Nickel Records; several suggestions were made and, says DeYoung, Styx was chosen because it was "the only one that none of us hated".
* James "J.Y." Young – vocals, guitar, keyboards (1972–present)
* Tommy Shaw – vocals, guitars, mandolin, autoharp, talkbox (1976–1983, 1995–present)
* Todd Sucherman – drums, percussion, vocals (1995–present)
* Lawrence Gowan – vocals, keyboards, guitar (1999–present)
* Ricky Phillips – bass guitar, vocals (2003–present)
* Chuck Panozzo – bass guitar, vocals (1972–present; is currently a part-time member, appearing as a "guest musician" every so often)
* Dennis DeYoung – vocals, keyboards, accordion (1972–1999)
* John Panozzo – drums, percussion (1972–1996)
* John Curulewski – guitar, vocals, autoharp, synthesizers (1972–1975)
* Glen Burtnik – guitar, keyboards, vocals (1990–1992) / bass guitar, vocals (1999–2003)