DeWitt's decision locks in his $1.1 million salary that he agreed to when he avoided arbitration with the Cubs in January. Had DeWitt elected to not accept the assignment he would have become a free agent and his $1.1 million deal would have been voided.
When infielder Adrian Cardenas was claimed off waivers from the Oakland A's earlier this month, DeWitt was designated for assignment to open a 40-man spot. DeWitt was not picked up by any team during a 10-day waiver period.
The left-handed hitter appeared in 121 games last season mostly as a backup at second base, third base and left field, batting .265 with five home runs and 26 RBIs. He lost a battle for the starting second base job last spring to Darwin Barney.
As a non-roster player this spring, DeWitt is expected to compete for a utility role.