When Is the Best Time to Visit Koh Samui?
The best time to visit Koh Samui is January to March for dry weather and calm seas. For lower prices and fewer crowds, May to July is a great alternative. October and November are the rainiest months.
So What Does That Actually Mean for Your Trip?
We’re a family of four who’ve been living in Thailand since 2019. We recently moved back to Koh Samui after spending a couple of years on the neighboring island Koh Phangan. And let me tell you—we’ve seen every single month on Samui. Sunshine, floods, heatwaves, downpours… we’ve been through it all.
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🏡 Check for special deals at Hyatt Regency Samui here.
🏝️ Read about the best family areas and things to do in Samui with kids.
What’s the Best Month to Visit Koh Samui?
The best time to visit Koh Samui is January to March if you want dry weather, blue skies, and calm seas.
If you’re looking for fewer crowds and better hotel deals, May to July is a great alternative.
The rainiest months are October and November, which you should try to avoid.
Here’s the quick summary:
– Best weather: January to March
– Best value: Mid-March to July
– Avoid if possible: October and November
– Still good but unpredictable: August and September
– Christmas holidays: Late December is a great time to come, but plan ahead
What Is the Worst Time to Visit Koh Samui?
Honestly, the worst time to visit Koh Samui is October and November.
This is peak monsoon season. Rain can last for hours or even days. Seas are rough, ferry crossings get canceled, and some tours stop operating altogether.
That doesn’t mean the island shuts down. If you’re looking for peace, low prices, and don’t mind rain, these months can still have their charm.
Verdict:
Worst for beach weather and island hopping.
Best for slow travel, quiet cafés, and deep hotel discounts.
What’s the Weather Like in Koh Samui Month by Month
January in Koh Samui
January is one of the most popular months to visit. The skies are usually clear, the humidity is lower, and the sea is calm.
- Weather: Dry, breezy, and beautiful
- Average temp: 79–86°F (26–30°C)
- Rainfall: Low, around 60 mm
- Sunshine: About 8 hours a day
- Mid-range hotel price: $163 (€150)
It’s high season, so the island gets busy. If you’re coming in January, book early.
⚠️ Note: In 2025, the rainy season decided to hang around until mid-January. So even during “dry season,” the weather can be unpredictable. In 2026, it feels much drier so far.
February in Koh Samui
February is one of the driest and sunniest months. Great for swimming, snorkeling, or just doing nothing on the beach.
- Weather: Peak weather, peak crowds
- Average temp: 79–88°F (26–31°C)
- Rainfall: Very low
- Sunshine: About 9 hours a day
- Mid-range hotel price: $163 (€150)
Expect crowds and higher prices. It’s still totally worth it if you want nearly perfect weather.
March in Koh Samui
March is hotter but still mostly dry. The beaches are less crowded than earlier in the year.
- Weather: Still sunny, getting hotter
- Average temp: 81–90°F (27–32°C)
- Rainfall: Low
- Sunshine: Around 9 hours a day
- Mid-range hotel price: $130 (€119)
If you want sun without peak season chaos, March is a great time to come.
April in Koh Samui
April is hot and humid—but fun. Songkran (Thai New Year) brings a full-on water fight to the streets.
- Weather: The hottest month of the year
- Average temp: 81–91°F (27–33°C)
- Rainfall: Still low, but humidity is up
- Sunshine: Around 8 hours a day
- Mid-range hotel price: $120 (€110)
Great if you love sunshine and don’t mind the heat. Also cheaper than earlier months.
May in Koh Samui
May is still hot, but you’ll start to see more clouds and occasional tropical showers.
- Weather: Hot with a chance of rain
- Average temp: 82–91°F (28–33°C)
- Rainfall: Moderate
- Sunshine: Around 7 hours a day
- Mid-range hotel price: $110 (€100)
Tourist numbers go down, and so do hotel rates. It’s a nice balance if you’re flexible.
June in Koh Samui
June is a great mix of good weather and fewer people. Some clouds and showers, but still plenty of beach time.
- Weather: Calm and mostly sunny
- Average temp: 82–90°F (28–32°C)
- Rainfall: Moderate
- Sunshine: Around 7 hours a day
- Mid-range hotel price: $100 (€91)
If you’re looking for a peaceful trip without crowds, June delivers.
July in Koh Samui
July brings slightly more rain but nothing too dramatic. Most days are sunny or partly cloudy with short showers.
- Weather: Warm and humid
- Average temp: 82–90°F (28–32°C)
- Rainfall: Moderate
- Sunshine: Around 6 hours a day
- Mid-range hotel price: $110 (€100)
Still a good time to visit, especially for families on school holidays.
August in Koh Samui
August feels a bit unstable. Some years it’s lovely, others are wetter. It’s still very warm and lush.
- Weather: Rain is coming, but slowly
- Average temp: 82–90°F (28–32°C)
- Rainfall: Increasing
- Sunshine: Around 7 hours a day
- Mid-range hotel price: $120 (€110)
Good for flexible travelers who don’t mind a little rain.
September in Koh Samui
September is the start of wetter times. Still warm, but the rain gets more regular.
- Weather: Warm and wet
- Average temp: 81–90°F (27–32°C)
- Rainfall: High
- Sunshine: Around 6 hours a day
- Mid-range hotel price: $100 (€91)
It’s not ideal for beach lovers but great if you’re on a budget or need quiet.
October in Koh Samui
October marks the start of the full rainy season (also called monsoon season). You might get lucky with a few dry days—but don’t count on it.
- Weather: Rainy season begins
- Average temp: 81–88°F (27–31°C)
- Rainfall: Heavy
- Sunshine: Around 5 hours a day
- Mid-range hotel price: $90 (€82)
Best for those who don’t mind staying indoors or finding cozy cafes.
November in Koh Samui
November is usually the wettest month. It’s not the best time for beach holidays, but it can be peaceful if you’re into slow travel.
- Weather: Peak rainy season
- Average temp: 79–86°F (26–30°C)
- Rainfall: Very heavy
- Sunshine: Around 4 hours a day
- Mid-range hotel price: $95 (€86)
Expect travel delays and boat cancellations, but great deals on places to stay.
December in Koh Samui
Early December can still be rainy, but by mid-month the dry season starts to return. Just in time for the holidays.
- Weather: Rainy start, sunny finish
- Average temp: 79–86°F (26–30°C)
- Rainfall: Moderate to low
- Sunshine: Around 6 hours a day
- Mid-range hotel price: $150 (€137)
By Christmas, the beaches are back in business. Book early—it gets busy fast.
Where to Stay in Koh Samui
If you’re planning your trip to Samui and wondering where to stay, here are our two absolute favorite Hotels in Koh Samui:
Anantara Bophut Resort
- From $250 (€232) per night (Premier Room)
- Lush gardens, calm beach, close to the Fisherman’s Night Market, read my review here!
Hyatt Regency Koh Samui
- From $230 (€212) per night (Family Room)
- Read my honest review here!
👉 You might also like my other Koh Samui articles:
– Best Family Resorts in Koh Samui
– Red Baron Sunset Cruise in Samui – Family Review
– Is Samui Elephant Sanctuary Ethical?
Key Takeaways
- January to March = best weather
- May to July = best balance of price and sunshine
- October and November = rainiest months
- Samui’s seasons are different from Phuket
Final Thoughts on the Best Time to Visit Koh Samui
I’m writing this article in early June, from a sunny café on Koh Samui. The sky’s clear, and I’m about to head to the beach with my daughters. That’s what I love about this time of year. It’s not as crowded, prices are lower, and you still get plenty of beautiful days like this.
But Koh Samui’s weather isn’t always predictable. We’ve had dry spells in November and surprise rain in January. If you can stay flexible and go with the flow, you’ll find your own perfect time to visit.
What’s your favorite time of the year to visit Koh Samui? Please let me know in the comments.
Thank you for reading and for making me part of your day! Yours, Lulu
FAQ – Best Time to Visit Koh Samui
Is Koh Samui a year-round destination?
Yes, but not every month is beach-perfect. Weather varies a lot more than people expect.
What is the worst time to visit Koh Samui?
October and November. Heavy rain, rough seas, and frequent boat cancellations.
Is August a good time to visit Koh Samui?
It can be. Some years are sunny, others wet. Best for flexible travelers.
When is the rainy season in Koh Samui?
Usually from October to December, peaking in November.
Is Koh Samui good with kids during low season?
Yes, if your hotel is comfortable and you plan around rain.
Is November a Good Time to Visit Koh Samui?
Short answer: usually no. November is typically the wettest month on Koh Samui. This is when the rainy season peaks. You can expect heavy downpours, grey skies, and rough seas. Boat trips are often canceled, and beach days are unreliable.
That said, November is quiet. Cafés are calm, roads are empty, and hotel prices drop. If you don’t mind rain and enjoy slow travel, it can still work. Just don’t come for a classic beach holiday.
Is August a Good Time to Visit Koh Samui?
August is a hit-or-miss month.
Some years are sunny with only short tropical showers. Other years feel noticeably wetter. It’s always warm, the island is lush and green, and prices are lower than in high season.
August is popular with families due to school holidays. You’ll still get beach days, but you need flexibility and a backup plan for rainy afternoons.
Is April a Good Time to Visit Koh Samui?
Yes, if you can handle the heat.
April is one of the hottest months on Koh Samui. Rainfall is still low, but humidity is high, and midday heat can be intense. Early mornings and late afternoons are the most comfortable times to be outside.
April is also when Songkran (Thai New Year) takes place. The island turns into a giant water fight. Loud, fun, chaotic, and unforgettable. We celebrated Songkran here with our kids and loved it.
