It’s a fact – Koh Samui is one of the most beautiful destination on the planet. (If you don’t believe me, take a look at these 10 swoon-worthy villas in Koh Samui). But even in paradise, a little rain must fall – or if you happen to be visiting this Thai island during rainy season, a heck of a lot of rain must fall. Because weather in tropical destinations can vary drastically, it’s important to consider when is the best time to visit Koh Samui before leaping at those dirt-cheap flights.

Rainy Season

The dreaded rainy season in Koh Samui takes place roughly between September and November (though rain starts to fall as early as May). The heaviest rains fall in October and November. Though a lot of people shy away from Koh Samui all together during the wet season, rain showers are often short-lived and it doesn’t necessarily rain every day. Still, if you’re dead set on returning home with a bronze tan or want to do some snorkelling, this is not the best time to visit as the rain significantly reduces underwater visibility.

Best time to visit Koh Samui, Thailand

Dry Season

As far as weather goes, the dry season is the best time to travel to Koh Samui. Dry season spans from December to February. As you might have guessed, weather is dry but not unbearably hot. As the dry season also overlaps with Christmas and New Year, it’s by far the most popular time of year to visit Koh Samui. If you want to experience the dry season magic, it’s best to plan ahead and book your preferred accommodation way in advance to avoid disappointment.

Hot Season

The hot season in Koh Samui spans from March until August. The weather is nice and sunny and very, very hot. Unlike in the rainy months, there’s nothing stopping you from exploring the island and its waters during the hot season – provided you can stand the +32°c (and over!) heat. As the rains begin to fall around May, the daily heat is interrupted by thunderstorms that usually take place in the afternoon.

Beach Republic Ocean Club Lamai Koh Samui Thailand

Festivals and Holidays

Besides the weather, it’s also important to consider the event calendar when deciding when to visit Koh Samui. International holidays like Christmas and New Year draw in huge crowds, meaning prices are at their peak and good accommodation can be hard to come by if you’re booking last minutes.


Songkrang is the most important local festival and takes place in April. Songkrang is the Thai New Year and celebrations include a massive water fight. It depends on your personal taste if travelling to Koh Samui during Songkrang is a pro or a con. On the other hand, you get to join in a unique celebration and take part in a massive water fight. Then again, it does get crowded and there might be traffic jams and delays as local people flock home to spend the holiday with their families.

Is Songkrang a good time to visit Koh Samui? Think of it as spending Chinese New Year in Peking or New Year’s Eve in New York and decide for yourself.

Songkrang water festival in Thailand


The time you decide to travel to Koh Samui can affect the trip’s price tag drastically. During high season (December – February, plus a smaller peak in July-August), prices typically hike up exponentially, so it’s not the best time to visit Koh Samui on a budget. It’s also good to remember that a lot of villas increase their minimum stay during high season. For some places, the minimum stay could be up to two weeks, so an impromptu mini-break might not be in the cards.

Rainy season drags down prices and offers the added perk of fewer tourists, meaning you might just have some of those paradise beaches all to yourself. It’s wise to consider, though, how you will spend those rainy hours stuck inside your villa or hotel and wether it’s worth it in the end. If you still feel tempted to travel during the lull, we’ve previously covered some indoor activities you might try on another Thai island – most of them are applicable to Koh Samui as well.

If you’re looking for the best value and most bang for your buck, consider travelling to Koh Samui during shoulder season. These fringe windows fall right before and after high season, meaning weather conditions are good but the crowds haven’t descended yet (or have already headed home). This combination means you get to enjoy great Koh Samui weather without spending a fortune. Roughly put, Koh Samui shoulder season falls into late February and March, from April to June and early December.

Planning a trip to Thailand but not sure where to start? Ministry of Villas offers hand selected collection of luxury villas in Koh Samui and beyond. We also provide personalised service that goes beyond what you see online. Contact our team to find out more.

  • Villa Enquiry

  • This field is for validation purposes and should be left unchanged.