The 24-year-old arrived at Kingsholm from Premiership rivals Leicester Tigers in 2012. Twelvetrees has five international caps and was called up to the British and Irish Lions squad for their victorious tour of Australia this summer.
Billy the match winner
Centre Billy Twelvetrees scored the last-minute match-winning penalty for Gloucester in their 26-24 victory against Northampton on Saturday.
“I’m happy playing here and it’s a great feeling to put on the Cherry and Whites shirt,” he told BBC Points West.
“To do it with your friends, and the sort of players we have here, is terrific. “It was an easy decision for me and I just wanted to get it sorted.” Twelvetrees came through Leicester’s academy system and broke into the first team in 2009. Now in his second season at Gloucester, the inside centre has made a total of 53 Premiership appearances, scoring 225 points. He was called up to Stuart Lancaster’s Six Nations squad this year and earned his first full international cap in the Calcutta Cup clash with Scotland at Twickenham, in which he scored a try. And, after impressing on the tour of Argentina, the number 12 went on to join the Lions squad as injury cover.