Coffman was signed by the Colts on Tuesday, Kevin Bowen of Colts.com reports.
Coffman was with the Colts for training camp and the preseason, but he failed to land a spot on the final roster. With top TE Dwayne Allen (ankle) considered week-to-week and likely to miss at least one game, Coffman will provide depth behind Jack Doyle and Erik Swoope.