There are
646 mi
from St Louis, MO to North Richland Hills, TX
That's the driving distance. It would take 12 hours 5 mins to go from St Louis, Missouri to North Richland Hills, Texas.
The flight distance (direct flight from St Louis, MO to North Richland Hills, TX) is 561.46 mi.
646 mi = 1,040.21 kms