On April 15, 2013, the New Orleans Saints signed Wallace to a one-year deal. On August 19, 2013, he was released by the Saints.
On August 22, 2013, he signed a one-year deal with the San Francisco 49ers. A week later on August 29, 2013, he asked for his release. He later said that (contrary to some news reports) he was not retiring, but had decided to leave the 49ers because he felt they were not giving him a chance to make the team, and had signed him only to pressure their principal backup quarterback, Colt McCoy, to accept a pay cut.
On September 2, 2013, Wallace signed with the Green Bay Packers. He first played for the Packers on November 4, 2013 after an injury to the left shoulder of Aaron Rodgers in the first quarter of the Monday night game against the Chicago Bears. His first start for the Packers was on Sunday, November 10, 2013 against the Philadelphia Eagles. During the game's opening drive, Wallace suffered a season-ending groin injury and had to leave the game. He was replaced by quarterback Scott Tolzien, who made his first regular-season NFL appearance.