There are
1,231 mi
from San Clemente, CA to Missoula, MT
That's the driving distance. It would take 20 hours 48 mins to go from San Clemente, California to Missoula, Montana.
The flight distance (direct flight from San Clemente, CA to Missoula, MT) is 947.08 mi.
1,231 mi = 1,981.87 kms