What is the easiest way to get to
Koh Tao?
From Bangkok The options of getting to Koh Tao from Bangkok can be overwhelming. Generally speaking, by far the easiest way to get here is by flying from Bangkok to Koh Samui (price around 3300 B) and from there catch a speed- or express boat (price around 350-550 B). Bangkok Airways have several departures a day from Don Muang Airport. Songserm Travel can be helpful with boat trips from Koh Samui, Chumporn and Surat Thani. If flying is beyond your budget, then I recommend taking the train to Chumporn and from there a speed- or express boat. Buy a combined ticket from Ban's office (price around 400-550 B) in the Bayon buliding on Kowsarn Rd or any of the small ticketing offices on Kowsarn Road in Bangkok. Check out all options. The State Railway of Thailand should be helpful with specific enquiries and timetables. Apart from the above options, there are a million more airconditioned buses and minibuses going from Bangkok down south.

From Phuket and Krabi
Either fly to Koh Samui or take bus or minibus to Surat Thani, the main connection to Koh Tao and it's sister islands in the Gulf of Thailand.