There are
1,610 mi
from Missoula, MT to Merrillville, IN
That's the driving distance. It would take 1 day 4 hours to go from Missoula, Montana to Merrillville, Indiana.
The flight distance (direct flight from Missoula, MT to Merrillville, IN) is 1,366.32 mi.
1,610 mi = 1.61 kms