Koh Phangan is most easily accessed via Koh Samui International Airport and flights to and from Bangkok are operated by Bangkok Airways around the clock. Direct International flights to Koh Samui operate from Singapore, Hong Kong, Pnom Phen, Hanoi and other major cities website: www.bangkokair.com
From Koh Samui, there are several ferries per day (30 - 40 minutes travel). At the arrival counter of the airport at Koh Samui, boat tickets as well as transfer to the pier are provided. The ferry goes directly to Tong Sala, which is the main village on the island.
It is also possible to travel via Surathani, the closest town on the continent, which is served by several low cost airlines (NokAir / AirAsia). From Surathani, there are several boats to the island (1.5 - 3hrs travel).