There are
1,720 mi
from Amarillo, TX to Seatac, WA
That's the driving distance. It would take 1 day 6 hours to go from Amarillo, Texas to Seatac, Washington.
The flight distance (direct flight from Amarillo, TX to Seatac, WA) is 1,350.80 mi.
1,720 mi = 1.61 kms