Phillips, a 6-2, 225-pound sophomore from Signal Mountain, Tenn., did not play during the 2015 season after recovering from offseason surgery. He was listed as UK's third-team quarterback behind Patrick Towles and Drew Barker for most of the season.
Towles, who lost his job to Barker late in the season, opted to transfer to Boston College after graduating from UK this month.
Phillips, who was recruited primarily by the previous Kentucky staff, played in three games as a redshirt freshman in 2014. He completed two passes for 45 yards in the Cats' win over UT Martin.
The departure leaves UK with only one scholarship quarterback heading into spring practice -- Barker, who will be a third-year sophomore.