There are
1,236 mi
from Irvine, CA to Billings, MT
That's the driving distance. It would take 21 hours 50 mins to go from Irvine, California to Billings, Montana.
The flight distance (direct flight from Irvine, CA to Billings, MT) is 969.40 mi.
1,236 mi = 1,988.50 kms