Miles between Longmont, CO and Allen, TX

There are
816 mi
from Longmont, CO to Allen, TX

That's the driving distance. It would take 15 hours 5 mins to go from Longmont, Colorado to Allen, Texas.

The flight distance (direct flight from Longmont, CO to Allen, TX) is 675.18 mi.

816 mi = 1,313.09 kms