December · Thailand
Best time to visit Koh Samui in December Weather, crowds & prices
Weather in Koh Samui in December
Average temperature 24°C, 171 mm of rain, about 27 days with 6+ hours of sunshine and 80% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
December score
7.1/10
Ranked #10 of 12 months
- Avg temp
- 24°C
- Rainfall
- 171 mm
- Humidity
- 80%
- Days with 6h+ sun
- 27
- Crowd Density
- Quiet / Uncrowded
- Average Expenses
- $$ · Moderate Cost ($$)
December in Koh Samui scores 7.1/10 for beach and coastal travel - ranked #10 of 12. Expect around 24°C, 171 mm of rain, and roughly 27 days with 6+ hours of sunshine this month.
Koh Samui's ring road links Chaweng's beach, Bophut's Fisherman's Village, and the Big Buddha on the north coast.
December in Koh Samui: strong conditions, 10th of 12
December averages 24°C (75°F) — warm enough for beach and boat plans, still short of the heat that pushes sightseeing into early morning.
Monthly rainfall reaches 171 mm — wet for this destination — but about 27 days with 6+ hours of sunshine still break through, so keep one indoor fallback in the plan.
It scores 7.1/10 here, 10th of 12 months, against 9.3/10 in the destination's best month.
Pack light clothing, swimwear and real sun protection, a proper rain shell rather than an umbrella.
Figure on mid-season pricing, with crowds are light for this destination.
Flexible dates? March scores 2.2 points higher here — enough to change the trip.
Frequently asked
- What is the weather like in Koh Samui in December?
- In December, Koh Samui averages 24°C, 171 mm of rain, and about 27 days with 6+ hours of sunshine. Its climate-comfort score is 7.1/10.
- Is December a good time to visit Koh Samui?
- December earns a 7.1/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Koh Samui in December?
- Expect about 171 mm of rain in December. Average humidity is 80% and there are about 27 days with 6+ hours of sunshine.
Curated in Koh Samui
Tickets & experiences
Things to do in Koh Samui
Koh Samui, Thailand. Live activities and tours from GetYourGuide, matched to this destination.