A backup for regular catcher Salvador Perez in his only season with the Royals, Kottaras batted just .180 but half of his 18 hits were for extra bases, including five home runs. He also drew 24 walks in 126 plate appearances for a .349 on-base percentage. A left-handed hitter, he was 2-for-8 as a pinch-hitter.
Manager Ned Yost said that Kottaras' defense was much better than he expected. He was in 46 games, including 29 starts.
Kottaras was designated for assignment Thursday to make room on the 40-man roster for pitcher Jason Vargas, signed as a free agent. Finances may have played a role, too, because Kottaras made $1 million last year and likely was in line for a substantial raise as an arbitration-eligible player.
His departure leaves Brett Hayes and Francisco Pena as the on-roster candidates to back up Perez.
Kottaras, 30, previously played for Boston, Milwaukee and Oakland.
Dick Kaegel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.