There are
1,846 mi
from St Charles, MO to Pullman, WA
That's the driving distance. It would take 1 day 8 hours to go from St Charles, Missouri to Pullman, Washington.
The flight distance (direct flight from St Charles, MO to Pullman, WA) is 1,451.04 mi.
1,846 mi = 2,970.78 kms