Season guide · Koh Samui · Thailand
Koh Samui in the monsoon
October–January: weather, crowds, prices and the best things to do this time of year.
Updated By the AMZBooking editorial team
Photo: Abrget47j, CC BY-SA 3.0
Quick answer
Heavy rain peaks in November, with rough seas and cancelled boat trips; conditions improve through January. Expect highs up to 31°C (88°F) and lows around 24°C (75°F), with about 65 rainy days across October–January.
Key facts
- Months
- October–January
- Temperatures
- 24°C (75°F) to 31°C (88°F)
- Rainy days in the season
- About 65
- Sea
- 27°C (81°F) to 28°C (82°F)
- Crowds
- Moderate
- Hotel prices
- Average
Weather in the monsoon
| Month | High | Low | Rainy days | Daylight | Crowds |
|---|---|---|---|---|---|
| January | 29°C (84°F) | 24°C (75°F) | 10 | 11.6 h | 4/5 |
| October | 31°C (88°F) | 24°C (75°F) | 19 | 11.9 h | 2/5 |
| November | 29°C (84°F) | 24°C (75°F) | 21 | 11.7 h | 1/5 |
| December | 28°C (82°F) | 24°C (75°F) | 15 | 11.6 h | 4/5 |
Compared with the rest of the year: average highs of 29°C (84°F) against a yearly 31°C (88°F), and 65 of the year's roughly 142 rainy days fall in these 4 months. Crowds rate 3/5 and hotel prices 3/5 on average.
What's on in the monsoon
Recurring events; dates move from year to year, so confirm with the organiser.
- January: Chinese New Year in Nathon (January or February)
- October: Ok Phansa — end of Buddhist Lent (usually October)
- November: Loy Krathong — floating offerings on the sea (usually November full moon)
- December: Christmas and New Year beach parties
Good choices for the monsoon
Experience · Chaweng
Thai cooking class
Book a morning class with a market visit so you learn about southern Thai ingredients such as fresh turmeric.
- Time needed
- Half a day
- Cost
- Mid-priced
- Food
- Kids
- Rainy day
- Couples
Experience · Chaweng
Muay Thai fight night
Stadiums in Chaweng and Lamai stage regular bouts of Thailand's national sport, with traditional music and pre-fight rituals, from local youngsters to experienced fighters.
- Time needed
- 2–3 hours
- Cost
- Mid-priced
- After dark
- Rainy day
- Active
Day trips in the monsoon
- Koh Tan and Koh Madsum (About 20–30 minutes by longtail) — Two small islands off Samui's south coast with calm, shallow snorkelling reefs, quiet beaches and simple seafood restaurants.
- Ang Thong National Marine Park (About 1–2 hours by boat) — An archipelago of more than 40 limestone islands with kayaking among the karsts, snorkelling, a steep climb to the viewpoint on Koh Wua Talab and the enclosed Emerald Lake on Koh Mae Ko.
What to pack
- Light, breathable clothes, a sun hat and high-factor sunscreen
- A compact umbrella and waterproof shoes — rain is frequent
- Comfortable walking shoes
Other times of year
Questions travellers ask
+Is the monsoon a good time to visit Koh Samui?
It is a trade-off: Heavy rain peaks in November, with rough seas and cancelled boat trips; conditions improve through January. The best months overall are February–April and June–August.
+What is the weather like in Koh Samui in the monsoon?
Highs of up to 31°C (88°F) and lows around 24°C (75°F), with about 65 rainy days over the season.