On January 16, 2016, the Kansas City Royals signed Kennedy to a five-year, $70 million contract, with an opt-out clause built in prior to the 2018 season. Kennedy was happy to join the team, which he described as "an easy environment", and particularly enjoyed the reunion with his Yankees pitching coach, Dave Eiland. On the final day of spring training, Kennedy exited the mound shortly before the fourth inning with left hamstring tightness.
On January 16, 2016, the Kansas City Royals signed Kennedy to a five-year, $70 million contract, including an option for him to leave after the 2018 season. Kennedy was pleased to join the team, which he described as "a relaxed atmosphere", and particularly enjoyed reuniting with his former Yankees pitching coach, Dave Eiland. On the final day of spring training, Kennedy left the mound before the fourth inning due to a left hamstring strain.