Koh Samui
Koh Samui is Thailand's second-largest island, famous for its palm-fringed beaches, coconut groves and luxury resorts. From the famous Big Buddha temple to pristine white sand beaches like Chaweng and Lamai, this Gulf of Thailand gem offers the perfect blend of relaxation and adventure.
About Koh Samui
Koh Samui offers an incredible variety of experiences for every traveler. The island's 34 beaches range from bustling Chaweng with its vibrant nightlife to peaceful Maenam perfect for families. Don't miss the iconic Big Buddha at Wat Phra Yai, explore the stunning Ang Thong Marine Park on a day trip, or discover hidden waterfalls in the island's mountainous interior. The charming Fisherman's Village in Bophut hosts a famous Friday night market, while world-class spas and wellness retreats make Samui a top destination for relaxation.
Quick Facts
Population
63,000
Area (km²)
228.7 km²
Sunny Days/Year
250 days
Beaches
34
Coastline
80 km
Resorts
350
Dive Sites
25
Avg. Temperature
28°C
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Daylight, UV and air quality in Koh Samui
Live conditions, updated continuously — sun times calculated for this exact location.
- Sunrise
- 06:10
- Sunset
- 18:19
- Golden hour
- 17:51
- Blue hour
- 18:40
Sources: Open-Meteo and our own solar calculations
Climate in Koh Samui month by month
Long-term averages 1991–2020 — what the weather is normally like, not a forecast.
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Day | 25° | 25° | 26° | 27° | 27° | 27° | 27° | 27° | 26° | 25° | 25° | 25° |
| Night | 23° | 23° | 24° | 24° | 24° | 24° | 24° | 24° | 23° | 23° | 23° | 23° |
| Precipitation (mm) | 81 | 37 | 89 | 96 | 115 | 87 | 83 | 91 | 140 | 282 | 284 | 147 |
| Rain days (days) | 11 | 6 | 10 | 12 | 22 | 19 | 18 | 18 | 22 | 26 | 22 | 14 |
| Sunshine (h/day) | 10.5 | 10.8 | 10.8 | 11.1 | 10.7 | 10.1 | 9.8 | 9.7 | 9.2 | 8.9 | 9.2 | 9.8 |
| Colour shows how well the month suits a trip |
Source: Open-Meteo ERA5 reanalysis, 1991–2020
Chance of rain in Koh Samui month by month
How often it normally rains — share of days with at least 1 mm, averaged over 1991–2020.
Driest period
December – April
Driest month
February · 21%
Wettest month
October · 85%
Chance of rain
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain probability | 35% | 21% | 31% | 41% | 69% | 62% | 58% | 59% | 75% | 85% | 72% | 46% |
Rain days per month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain days (days) | 11 | 6 | 10 | 12 | 22 | 19 | 18 | 18 | 22 | 26 | 22 | 14 |
Source: Open-Meteo ERA5 reanalysis, 1991–2020
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Where to stay in Koh Samui
An interactive map of hotels and apartments in Koh Samui, from our partner Stay22.
Top Attractions
Big Buddha Temple
Iconic 12-meter golden Buddha statue at Wat Phra Yai with panoramic island views
Book ticketsAng Thong Marine Park
42 pristine islands with emerald lagoons, hidden caves and world-class snorkeling
Na Muang Waterfalls
Twin cascading waterfalls surrounded by lush jungle, perfect for swimming
Book ticketsGrandfather & Grandmother Rocks
Famous natural rock formations at Lamai Beach with local legend
Book ticketsFisherman's Village Bophut
Charming walking street with boutique shops, restaurants and night market
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Things to do in Koh Samui
Tours and activities in Koh Samui, from our partner GetYourGuide.
Best Beaches
Chaweng Beach
The island's most famous 7km stretch of powdery white sand with vibrant nightlife
Lamai Beach
Beautiful palm-fringed beach with calmer atmosphere and excellent snorkeling
Maenam Beach
Peaceful 4km beach with shallow waters, perfect for families and swimming
Silver Beach
Hidden gem with crystal-clear water and soft sand, ideal for relaxation
Chaweng Noi
Quieter southern extension of Chaweng with luxury resorts and pristine sand
Best Time to Visit
The best time to visit Koh Samui is from December to April when the weather is dry and sunny. Unlike Thailand's west coast, Koh Samui in the Gulf of Thailand has its wettest months from October to December. Peak season offers calm seas, perfect for island hopping to Ang Thong Marine Park and enjoying pristine beaches.
Climate Overview
Koh Samui has a tropical monsoon climate influenced by its Gulf of Thailand location, creating a different weather pattern than mainland Thailand. The island enjoys warm temperatures of 26-32°C year-round. The monsoon affects the island from October to December with heavy rainfall, while the rest of the year is mostly dry with occasional showers. The water temperature stays warm at 27-29°C, perfect for swimming and diving.
Monthly Weather Overview
| Month | High °CMax | Low °CMin | Rain mmmm |
|---|---|---|---|
January | 29° | 23° | 85 |
February | 30° | 24° | 30 |
March | 31° | 25° | 45 |
April | 33° | 26° | 75 |
May | 33° | 26° | 150 |
June | 32° | 26° | 100 |
July | 32° | 25° | 100 |
August | 32° | 25° | 95 |
September | 31° | 25° | 140 |
October | 30° | 24° | 260 |
November | 29° | 24° | 360 |
December | 28° | 23° | 200 |
Weather in Koh Samui
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