There are
1,835 mi
from Santee, CA to St Charles, MO
That's the driving distance. It would take 1 day 8 hours to go from Santee, California to St Charles, Missouri.
The flight distance (direct flight from Santee, CA to St Charles, MO) is 1,532.55 mi.
1,835 mi = 2,952.95 kms