There are
634 mi
from Rowlett, TX to Florissant, MO
That's the driving distance. It would take 11 hours 52 mins to go from Rowlett, Texas to Florissant, Missouri.
The flight distance (direct flight from Rowlett, TX to Florissant, MO) is 535.98 mi.
634 mi = 1,019.74 kms