He was also a football player in high school, excelling at wide receiver, but he gave up the sport to focus on basketball.

Singletary was Virginia's floor leader during their pivotal 2006–07 season in which the team moved from their old home at University Hall across the street to the 130 million dollar John Paul Jones Arena.

Virginia enjoyed perhaps its best season since 1994–95 with Singletary and senior J. R. Reynolds forming one of the most outstanding backcourt combinations in the history of Cavalier basketball.

Singletary was selected to the 2007–08 All-ACC team, making him, Bryant Stith, and Ralph Sampson the only three Cavaliers to be named all-conference three times in their careers.

Against Gonzaga on December 17, 2005, he scored a career-high 35 points, including four 3-pointers, and had six steals and six rebounds in an 11-point loss,[4] and was named ACC Player of The Week.

[5] Singletary was also a co-captain of the Cavaliers and was also named First-team All-ACC selection by SI.com, State Player of the Year and a first-team All-State selection by the VaSID, Player of the Year in Virginia and first-team All-State as selected by the Richmond Times-Dispatch, co-recipient of the Bill Gibson Cavalier of the Year Award (team MVP), co-recipient of the Sidney Young Memorial Trophy (team award to that athlete who exemplifies the highest qualities of leadership, cooperative spirit and unselfish service in the interest of athletics at the University of Virginia), and received the team's Most Assists Award.

Singletary became one of the elite point guards in the country his junior year, scoring in double digits in all but one game.

Along with backcourt mate J.R. Reynolds, he led UVA to its first NCAA tournament berth since 2001, where they played the University of Albany in the first round.

Singletary confirmed to head coach Dave Leitao that he would return for his senior year season just hours before the 5 p.m. draft withdrawal deadline.

[12] After undergoing offseason hip surgery, Sean Singletary was selected in the second round of the 2008 NBA draft with the 42nd pick by the Sacramento Kings.

[14] On December 10, 2008, he was traded once again along with Boris Diaw and Raja Bell to the Charlotte Bobcats for Jason Richardson and Jared Dudley.

[15] On March 9, 2009, the Charlotte Bobcats assigned Singletary along with Alexis Ajinça to the NBA D-League's Sioux Falls Skyforce.