Detroit also announced Monday that it has waived guard Reggie Hearn.
The 6-foot-4 Lofton played last season at New Mexico State, averaging 20.1 points per game. He appeared in four games for the Pistons this preseason.
Hearn played in one game this preseason. He appeared in three games for the Pistons in 2017-18, playing a total of seven minutes.
Detroit opens the season Wednesday night against Brooklyn.