Flight Tacoma International Airport departs from Seattle Tacoma International Airport at 11:05 and arrives at Houston George Bush Intercontinental Airport at 18:57.The flight has a short stop at Denver.
The flighttime is about 5h 52m. The distance travelled ("as the bird flies"): 3030 Km. So the average speed is roughly 516 Km.
There is an 2 hour time difference between Seattle and Houston