The workhorse route of southern travel — sleeper trains, cheap flights and every island bus connection in one province.
Find a room before you go.
If time matters, budget airlines fly Bangkok–Surat Thani in just over an hour, and combined flight-bus-ferry tickets continue to Samui or Phangan. If the journey is part of the trip, the sleeper train remains the backpacker classic — board at night, wake up among palm plantations.

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Several sleepers leave Bangkok each evening and reach Surat Thani (Phun Phin) early morning, timed for the island buses and the Khao Sok minivans. Book berths a few days out in high season.
Multiple daily budget flights from Don Mueang and Suvarnabhumi. Add the airport-to-pier bus and you can be on Koh Samui by early afternoon for less than you'd think.
Overnight coaches from the Southern Terminal are the cheapest way south. Choose the big-name companies for the better on-board experience.
Step-by-step transport guides for this stretch of the Gulf coast.