There are
638 mi
from Lawton, OK to South Sioux City, NE
That's the driving distance. It would take 11 hours 28 mins to go from Lawton, Oklahoma to South Sioux City, Nebraska.
The flight distance (direct flight from Lawton, OK to South Sioux City, NE) is 553.67 mi.
638 mi = 1,026.73 kms