The Climate and Best Time to Visit
The climate at Koh Samui is tropical and warm throughout the year. March and April are the hottest months with average temperatures of 34°C and 75% humidity.
The High Season is from December to August and temperatures are consistently around 28-32°C. July and August are the busiest months and therefore the most expensive when it comes to finding accommodation. March to September, outside of July and August, is the best time to visit as there are fewer tourists, accommodation is much cheaper, the weather is at its best, and the seas are calm.
The rainy season runs from November to January. November is normally the wettest and windiest month although through much of the rainy season it is only a cool, late afternoon shower. This is also when the waves are their biggest.
If you are interested in trying your luck at seeing a whale shark, they are most spotted here in March and April, and again in September and October. Check out our dive site descriptions for details of the conditions in the Koh Samui diving season.
How to Get There
Koh Samui, Thailand's third largest island is 21 km long and 25 km wide. It lies 60 km from the mainland in the Gulf of Thailand. It has a pretty little airport. Bangkok Airways and Thai Airways have daily flights from Bangkok, Phuket or Pattaya and these are the quickest and most comfortable way to get to the island.
There is a night train from Bangkok that goes to Surat Thani. From there you can transfer to the ferry port for Samui. It is best to take a sleeper carriage because the trains are very slow. It is advisable to book trains in advance as they are often fully booked. For tall people, you will find the bottom bunk more spacious.
The cheapest mode of transport though is the bus. There are different classes of bus on offer. The government VIP 24 seat buses are highly recommended. First class buses are comfortable enough but standard class buses are not good for long journeys. You can buy tickets direct to Koh Samui with the price including the ferry. We recommend against buying tickets from travel agents in Khao San Road.
It is a 10 hour journey from Bangkok to Surat Thani. The bus air-conditioning can be chilly so we recommend you take a sweater (VIP buses provide blankets). It is a 4 hour journey from Phuket to Surat Thani with regular departures. You can also buy the government bus tickets from Phuket direct to Koh Samui.
The standard buses are good if you want to make friends with interesting locals. They will stop on route every time that someone along the roadside raises an arm. This mode of transport is only recommended if you are on a tight budget and time is not a factor.
When the bus arrives at the ferry port you will need to choose a ferry. You may find it easier to book the ferry with a bus ticket that includes the transfer to the port.
The big standard ferry takes 2½ hours. It has seating and sunbathing areas and for a small surcharge there is even an air-conditioned cabin. There is a smaller express boat that rolls quite a bit in the sea. It is normally full of backpackers. There is also the Seatran Express from Surat Thani which takes 2 hours to get to Nathon Pier on Koh Samui. There is also a slow night ferry from Surat Thani.
We recommend you consider taking out insurance to cover your diving package and travel activities, including trip cancellation. See our insurance programme for a competitive price:

Where to Stay
There is a wide variety of accommodations on Koh Samui. Choices range from 5 star international beach resorts to budget guesthouses, and everything in between. There is sure to be something that suits your taste and pocket on hotelscombined.com, our affiliated hotel reservation specialists.
Make your browse and book from their full range of Samui resort options, use their on-line chat, or simply use your credit card to make a booking. And whichever option you select will be backed up with their 'Low Price Guarantee' to ensure you get value for money.
