Dickenson signed as a free agent with the BC Lions in 2003. During the 2003 season, in which he led the Lions into the playoffs with an 11-7, 4th-place finish in the CFL West Division, Dickenson's 36 touchdown passes and were the second-highest single season marks in Lions' history behind Doug Flutie. Dickenson was named Offensive Player of the Month for August 2003, was the CFL Player of the Week in Week 5, and was awarded the Jeff Nicklin Memorial Trophy as the CFL West Division's Most Outstanding Player.