The 34-year-old, an All-Star in 2010 with Toronto, hit 134 home runs with seven big league teams. He hit .225 in 32 games with Seattle and the Los Angeles Angels last year after playing for the New York Mets and Pittsburgh in 2013.
He says he wants to spend more time with his family. He hit .320 with one homer in 25 at-bats for the Braves in spring training.
Buck set career highs with 20 homers and 66 RBIs with Toronto in 2010. He played his first six seasons with Kansas City.
He would have gotten a $1 million contract if added to Atlanta's 40-man roster.