Flight Samui International Airport departs from Koh Samui Samui International Airport at 19:10 and arrives at Bangkok Suvarnabhumi Airport at 20:45.
The flighttime is about 1h 35m. The distance travelled ("as the bird flies"): 113 Km. So the average speed is roughly 71 Km.
The best day to arrive at Koh Samui is Tuesday and it would be best to avoid Thursday, as prices are on average 109.1% higher than on Tuesday. (Average prices, based on 1300717 datapoints.)
We have a lot more statistics for flights PG 184 and between Koh Samui and Bangkok.