Stewart was born at Kirklatch Farm, Pittenweem, in the East Neuk of Fife, Scotland, and raised in Sutton, London. Stewart (often called Stu) started playing piano when he was six. He took up the banjo and played with amateur groups on both instruments. Stewart, who loved rhythm & blues, boogie-woogie, blues and big-band jazz, was first to respond to Brian Jones's advertisement in "Jazz News" of 2 May 1962 seeking musicians to form a rhythm & blues group. Mick Jagger and Keith Richards joined in June, and the group, with Dick Taylor on bass and Mick Avory (later of the Kinks) on drums, played their first gig under the name the Rollin' Stones at the Marquee Club on 12 July 1962. Richards described meeting Stewart thus: "He used to play boogie-woogie piano in jazz clubs, apart from his regular job. He blew my head off too, when he started to play. I never heard a white piano player play like that before." By December 1962 and January 1963, Bill Wyman and Charlie Watts had joined, replacing a series of bassists and drummers.