There are
171 mi
from Gresham, OR to Seatac, WA
That's the driving distance. It would take 3 hours 26 mins to go from Gresham, Oregon to Seatac, Washington.
The flight distance (direct flight from Gresham, OR to Seatac, WA) is 135.08 mi.
171 mi = 274.68 kms