2007 Costanzo is promoted to AA-Reading Phillies in the Eastern League and hits 27 Home runs with 86 RBI and is selected to the Eastern League All-Star game. He is selected to play in the Arizona Fall League for top prospects.
Costanzo is called up to the majors with the Cincinnati Reds for the first time on May 12, 2012.[11] In his first Major League at bat, he hit a sacrifice fly to left field, which scored Ryan Hanigan from third base. On May 19, 2012, Costanzo got his first Major League Hit off of New York Yankees pitcher Iván Nova. Yankees shortstop Derek Jeter retrieved the baseball and tossed it into the Reds dugout.
On June 6, he was optioned back to Triple-A Louisville. On August 1, Costanzo was designated for assignment.[12]
Costanzo was inducted into the Coastal Carolina University Hall of Fame in fall of 2012.
On December 28, 2012, he signed a minor league deal with the Washington Nationals.[13] Costanzo was released by the Nationals in June 2013 and was signed by the Cincinnati Reds.
Costanzo represented Team Italy in the 2009 and 2013 World Baseball Classic.