There are
785 mi
from Longmont, CO to Haltom City, TX
That's the driving distance. It would take 14 hours 32 mins to go from Longmont, Colorado to Haltom City, Texas.
The flight distance (direct flight from Longmont, CO to Haltom City, TX) is 669.09 mi.
785 mi = 1,263.40 kms