Koh Samui is located roughly 690 kms and a one-hour flight from Bangkok. Thai Airways and Bangkok Airways offer cheap flights to Koh Samui airport regularly. Air travelers may also choose to take a flight on Singapore Airlines or Virgin Australia into nearby Phuket International Airport and then take a small plane over to Koh Samui on Bangkok Airways.
If one prefers to take land transportation, buses depart from Bangkok and take about 13 hours to get to Koh Samui. The bus will make several stops before arriving and you can choose to take the trip during the day or overnight.
If an adventurous train ride sounds interesting, consider taking the train from nearby Surat Thani which is roughly 35 km away. Once completing the train ride, one can transfer to a nearby pier and take a ferry ride over to Samui. Trains typically have overnight sleepers and may be a more comfortable option than a bus. Ferries that depart Don Sak are able to accommodate vehicles for those that choose to rent a car while on the mainland. One can reach Koh Samui by boat. Typically, boat transfers will be included when one purchases a train or bus ticket with the ferry combination option. Otherwise, boats can be boarded from Surat Thani, Koh Pha Ngan and Koh Tao. The boats arrive on one of four terminals located on Koh Samui.