The best month to arrive at Koh Samui is November and the most expensive month to fly is August. (Average prices, based on 912 datapoints.)
The best day to arrive at Koh Samui is Wednesday and it would be best to avoid Friday, as prices are on average 76.67% higher than on Wednesday. (Average prices, based on 435 datapoints.)
At Koh Samui the most flights depart around 11:00. (Hourly flights, based on 1018 datapoints.)
From Koh Samui it is on average the cheapest to fly to Bangkok and to Bangkok. (Average prices, based on 592 datapoints.)