Most people enter Thailand by flying into Bangkok. From Bangkok there are three main options for getting down to Koh Tao island.
• The fastest but most expensive route: Fly to Samui.
You can pickup flights from Bangkok direct down to Koh Samui from around 4,000 baht, depending on the season and the time of the flight. From Samui take one of the high speed ferries across to Koh Tao island (Lomprayah Catamaran or Seatran) - these cost about 550 baht per person and take about an hour and forty five minutes.
If you shop around you may even be able to get a flight direct from your country of origin to Samui, cutting out the Bangkok bit. You can book flights on the internet directly with Bangkok Air.
NB. If you want to get to Koh Tao on the same day as you arrive in Samui ensure you have a flight arriving by 3:30pm as the last ferry over to Koh Tao departs Samui at 5pm. This is a Lomprayah ferry, however Lomprayah aren't listing this ferry on their website at present. You can book this through the 12Go.asia website.
• Flying to Chumphon or Surat Thani
Budget flights from Bangkok to Chumphon are available through the Nok Air company who also offer flights to Surat Thani.
• The compromise : Train to Chumphon
Thailand has a great rail service. From the airport you can get a meter taxi to the main Hualamphong train station in town (costing about 400 baht) or you can now take a train from the airport to the main train station. From Hua Lamphong train station you can catch a comfortable overnight train down to Chumphon. You can get a bed in an air conditioned carriage for less than 1,000 baht, waking up fresh at your destination in the morning!
From Chumphon you take a high speed ferry to Koh Tao island the same morning. This will take about an hour and forty five minutes to get to Koh Tao, however be aware that the train will arrive in Chumphon usually between 4 and 5am and then there is a 30 minute transfer to the pier in Chumphon and then the ferry doesn't depart until 7am (during high season the Lomprayah company do often put on an additional earlier ferry).
You often have to book a couple of days ahead especially around weekends & holidays and you have to book at least one week in advance when booking trains through the 12Go.asia website, if you are traveling in less than a weeks time then you can also drop into a train station to see if they have tickets available.
• The budget route : Bus from Bangkok
Even this isn't too bad. From the airport get a meter taxi to Khao San Road or a train to close to Khaosan Road and then take a metered taxi from there. The Lomprayah and Seatran combined bus and boat tickets depart from around Khaosan Road and will take you directly to Koh Tao. This will be an overnight bus ride to Chumphon or Lang Suan in the case of Seatran, then boat the rest of the way and should cost around 1000 baht all in.
Every travel agent will be able to book these tickets in for you or you can book it in again via 12Go.asia.
If you are coming from the south or the islands on the west coast
You can catch a ferry from Surat Thani, or just outside at Don Sak pier. You can catch either a ferry with the Songserm Express company, which depart at 10:00 or take the Lomprayah service from Surat Thani to Koh Tao, again you can book this in via 12Go.asia. There are also night boats that run providing the weather isn't too bad which depart at 23:00. The cheapest option is the night boat, followed by the somewhat misleadingly named Songserm Express which takes about 6 1/2 hours. The Lomprayah catamaran service is the quickest but also the most expensive option, but is our recommendation for this trip. If you are planning on traveling through the islands and then onwards up to Bangkok then enquiring about the Lomprayah's Buffet Ticket is worthwhile as you will save money and be able to stop off at Koh Samui, Koh Phangan, Koh Tao and Hua Hin on your way to Bangkok.
Booking in advance online links
If you would like to book your travel arrangements before arriving in Bangkok, which is advisable especially in high season and around the Full Moon parties on Koh Phangan.
You can book in all Train, Bus & Boat tickets via 12Go.asia they will give you up to date availability and they don't change their prices around the Full Moon Parties.
Remember however you must book 84 hours in advance for train tickets. If you are booking on the 12Go.asia website you can see the different schedules for ferries and buses etc You can also book in the Seatran bus and ferry tickets just 12 hours in advance and the Lompray bus and ferry tickets just 48 hours in advance through the 12Go.asia
NB. As general travel advice ensure to keep your valuables on you in your hand luggage as there have been numerous reports of people having things stolen especially on the overnight buses used by the Songserm company.