Mathis is set to earn $1.5 million in 2012, Litsch is signed for $975,000 and McGowan will make $600,000.
Toronto also tendered contracts to its remaining six arbitration-eligible players: right-handers Casey Janssen, Brandon Morrow and Carlos Villanueva; second baseman Kelly Johnson; and outfielders Colby Rasmus and Ben Francisco.
The 26-year-old Litsch went 6-3 with a 4.44 ERA in 28 games last season. He began the year in the rotation before eventually making a transition to the bullpen. He's expected to assume a similar role with manager John Farrell's team in 2012.
McGowan became a heartwarming story for the Blue Jays in 2011. The native of Savannah, Ga., made his return to the Major Leagues following a three-year absence caused by multiple surgeries.
The 29-year-old went 0-2 with a 6.43 ERA in five games, and he is expected to compete for the No. 5 spot in the rotation during Spring Training. McGowan is 20-24 with a 4.80 ERA in 374 2/3 career innings in the big leagues.
Mathis, whom Toronto acquired from the Angels during the offseason for lefty Brad Mills, is scheduled to back up J.P. Arencibia behind the plate.