There are
1,448 mi
from Allen, TX to Rancho Santa Margarita, CA
That's the driving distance. It would take 1 day to go from Allen, Texas to Rancho Santa Margarita, California.
The flight distance (direct flight from Allen, TX to Rancho Santa Margarita, CA) is 1,206.34 mi.
1,448 mi = 1.61 kms