Born in 1934 in Cardiff's Tiger Bay, Boston was the sixth of eleven children his father came from Sierra Leone, and his came from mother from Ireland. His ambition was to play for Cardiff Rugby team, but it was Neath who took him under his wing , Playing alongside him were Phil Jackson of Barrow, Brian Gabbitas of Hunslet, and Jimmy Dunn of Leeds as well as Phil Horrocks-Taylor, the future England rugby union fly half. It was after seeing Boston score six tries in the Army Cup Final against the Welsh Guards that Wigan signed him for £3,000 on Friday 13 March, 1953, which was not an unlucky day for rugby league; only for Hunslet, who had been pursuing him since he was sixteen.

When Boston was touring Germany with an Army XV when the news broke that he was to be one of Dickie Williams's Lions. Boston was the first black player the British had ever taken Down Under.
He was to make thirty-one test appearances for Great Britain before he was through, and he scored twenty-four tries at the highest level of the game. But it was for Wigan that he racked up the points endlessly, twice scoring seven tries in a match, against Dewsbury and Salford. Six times he went to Wembley with them, thrice as winner, and when he played his last match in the cherry and white, against Wakefield Trinity at the end of April 1968, he had given them 478 tries across fifteen years. He had a couple of years with Blackpool Borough before retiring as a fifteen-stone second-row forward, with 571 tries for club and country to his name; and only Brian Bevan had scored more in a British career.
In all he scored 571 tries in first class matches, the most by any British player, and only surpassed by the Australian Brian Bevan. In three seasons he scored 50 or more tries, with 60 in 1956-1957. He played 31 games for Great Britain, his last in 1963, scoring 24 tries. During his career, Wigan appeared in six Challenge Cup finals, winning three times.

Billy Boston has served Wigan, the club and the town where he settled, for most of his life. Today he can very often be seen alongside the coaching team at Wigan's games.
The great measurement of Billy Boston's natural ability is that after only six matches of rugby league, but he was only nineteen years old and he was picked for the 1954 Lions' tour Down Under. No one else ever came out of rugby union so fast. No one so young had ever gone on tour before. No one yet has scored his first century of rugby league tries in only sixty-eight matches.