There are
1,389 mi
from San Marcos, CA to Seagoville, TX
That's the driving distance. It would take 23 hours 53 mins to go from San Marcos, California to Seagoville, Texas.
The flight distance (direct flight from San Marcos, CA to Seagoville, TX) is 1,195.35 mi.
1,389 mi = 1.61 kms