Stewart played in only 55 games for the Cubs last season due to a wrist injury, hitting .201 with five home runs and 17 RBIs. Stewart agreed to terms earlier this month, tweeting out his return to Chicago.
"Glad to be healthy and back with the Cubs," he tweeted. "The support from the Cubs organization and the fans has been incredible. Thank you all so much,"
Terms of the deal were not released but a source close to the situation says Stewart will be paid $2 million with $500,000 in incentives.
The Cubs also announced the minor league signing of Korean pitcher Chang-Yong Lim to a two-year deal. Lim, 36, is coming off Tommy John surgery but posted at least 28 saves in four straight years from 2008-2011 before his injury ended his 2012 season prematurely. To make room on the 40-man roster for Stewart, pitcher Jeff Beliveau was designated for assignment.