White was born in St. Louis, Missouri, the son of a minister. He played college basketball at the University of Kansas, entering the NCAA Tournament and losing a double overtime thriller to Texas Western, currently known as the University of Texas at El Paso, in the Midwest regional final (Texas Western went on to win the championship).
After college, White played on the 1968 USA Olympic basketball team in Mexico, which went undefeated (9-0), beating Yugoslavia 65-50 in the title game.
After the Olympics, White was drafted in 1969 in the first round (9th pick overall) by the NBA's Boston Celtics, who at that time had just won their 11th championship in 13 years. However, before White even reported to training camp, the Celtics' center and player-coach Bill Russell announced his retirement. White would endure a rebuilding season while the Celtics got back on track, drafting Dave Cowens and trading for Paul Silas. Along with these two and veteran John Havlicek, White would be the cornerstone of two Celtic championship teams in the 1970s (1973–74 and 1975–76).
White went on to become one of professional basketball's first "iron men", playing in all 82 games for five consecutive seasons during the 1970s. White's skills included great defense, speed, an underrated jump shot, and team leadership.
The 1970 Celtics finished with the franchise's first losing record since 1951. With White leading the attack from the point guard position, the team returned to its winning ways in 1971. He was an All-Star for seven straight years from 1971 through 1977, finishing in the top ten in the league in assists from 1973-77. In 1974 and 1976, White helped lead the Celtics to the NBA championship and was named the most valuable player of the 1976 NBA Finals.
Perhaps the most exciting game White ever played was the triple overtime win against the Phoenix Suns in game 5 of those finals. White was the game's high scorer with 33 points, had a game high 9 assists, leading the Celtics to a 128-126 win. Logging an incredible 60 minutes of play time, only the Suns' Garfield Heard (61) played more minutes. Many claim it to be the greatest game ever played.
He was traded by the Celtics to the Golden State Warriors in 1979, and retired in 1981, with the Kansas City Kings. On Friday, April 9, 1982 his number 10 was hung from the rafters at the Boston Garden.
He returned to the Jayhawks as an assistant coach from 1982-83.
White continues to be involved in basketball and is currently director of special projects and community relations with the Celtics, while continuing to attend most home games.
Additionally, he appeared in two movies with diminutive roles: 1980's Inside Moves and 2007's The Game Plan, in which his son, actor Brian J. White, also starred.