Best time to visit Koh Samui for beach weather
When is beach season in Koh Samui? Warmest sea temperatures, best sunshine, and most reliable conditions for swimming and water activities.
Best month
February
Driest month of the year: 42mm of rain, long sunny days, and a slight easing of the January crush.
↑Statistically the least rainfall of any month — the most reliable weather window on the island
↑Slightly fewer visitors than January as European half-term crowds thin after early February
↑Ideal conditions for full-day sailing and snorkelling charters around the Ang Thong archipelago
All months ranked — Beach weather
Best match
Driest month of the year: 42mm of rain, long sunny days, and a slight easing of the January crush.
#1 for beach weather
Best match
Songkran brings Thai New Year festivities — warm, slightly wetter, but culturally unmissable.
#2 for beach weather
Best match
Shoulder season opens: still excellent weather, noticeably cheaper, and a more relaxed pace.
#3 for beach weather
Best match
Peak dry season: reliably sunny, warm, and the most visited month on the island.
#4 for beach weather
Strong option
Pre-monsoon transition: good value, quiet, but afternoon rain becomes a daily reality.
#5 for beach weather
Strong option
Second peak season: European summer holidays bring the crowds back to reliably sunny skies.
#6 for beach weather
Strong option
Still peak with good but slightly less reliable weather — August is busier than July.
#7 for beach weather
Strong option
Mixed month: decent value, quiet beaches, but frequent rain interrupts outdoor plans.
#8 for beach weather
Worth considering
Shoulder low season: heavy rain returns and the crowds evaporate — beach time is a lottery.
#9 for beach weather
Avoid
Monsoon peak: 305mm of rain and grey skies — the worst weather month on Koh Samui.
#10 for beach weather
Avoid
Second-worst weather month: monsoon still raging, many resorts closed or at skeleton service.
#11 for beach weather
Worth considering
Transitional: rain easing through the month, Christmas arrivals drive prices up before the payoff.
#12 for beach weather