Thailand

Best Time to Visit
Koh Samui

Visit in March — score 73/100 · avg high 82°F · 13 rainy days

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See how the best month changes based on your travel style

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Monthly Travel Scores

How we score

January

78°/72°F
20 rain days
11.5h daylight
High crowds
Average

February

#2
79°/72°F
16 rain days
11.7h daylight
High crowds
Average

March

#1
82°/74°F
13 rain days
11.9h daylight
Moderate crowds
Average

April

#3
83°/75°F
18 rain days
12.2h daylight
Moderate crowds
Average

May

83°/76°F
24 rain days
12.4h daylight
Moderate crowds
Below avg

June

83°/75°F
20 rain days
12.6h daylight
Moderate crowds
Below avg

July

83°/75°F
21 rain days
12.5h daylight
Moderate crowds
Average

August

83°/74°F
21 rain days
12.3h daylight
Moderate crowds
Average

September

81°/74°F
24 rain days
12.0h daylight
Moderate crowds
Below avg

October

79°/73°F
28 rain days
11.8h daylight
Moderate crowds
Average

November

78°/72°F
26 rain days
11.6h daylight
Moderate crowds
Average

December

78°/72°F
22 rain days
11.4h daylight
High crowds
Above avg

Monthly Weather Data

MonthScoreAvg °FHigh °FLow °FRain DaysPrecip (mm)DaylightCrowdsCost
January5075°78°72°2013011.5hHighAverage
February6275°79°72°166311.7hHighAverage
March7377°82°74°134111.9hModerateAverage
April6179°83°75°1810712.2hModerateAverage
May5279°83°76°2411412.4hModerateBelow avg
June6079°83°75°207412.6hModerateBelow avg
July5578°83°75°219512.5hModerateAverage
August5578°83°74°218112.3hModerateAverage
September5277°81°74°2413112.0hModerateBelow avg
October4976°79°73°2822011.8hModerateAverage
November4975°78°72°2628611.6hModerateAverage
December4374°78°72°2221611.4hHighAbove avg

Seasonal Breakdown

Spring

Score
62/100
High
83°F
Low
75°F
Rain days
18/mo
Crowds
moderate

Spring in Koh Samui (March, April, May) brings average highs of 83°F and lows of 75°F, with about 18 rainy days per month. Expect moderate tourist crowds and average accommodation rates. The overall travel score averages 62/100, with March being the strongest month of the season at 73/100.

Summer

Score
57/100
High
83°F
Low
75°F
Rain days
21/mo
Crowds
moderate

Summer in Koh Samui (June, July, August) brings average highs of 83°F and lows of 75°F, with about 21 rainy days per month. Expect moderate tourist crowds and average accommodation rates. The overall travel score averages 57/100, with June being the strongest month of the season at 60/100.

Fall

Score
50/100
High
80°F
Low
73°F
Rain days
26/mo
Crowds
moderate

Fall in Koh Samui (September, October, November) brings average highs of 80°F and lows of 73°F, with about 26 rainy days per month. Expect moderate tourist crowds and average accommodation rates. The overall travel score averages 50/100, with September being the strongest month of the season at 52/100.

Winter

Score
52/100
High
78°F
Low
72°F
Rain days
19/mo
Crowds
high

Winter in Koh Samui (December, January, February) brings average highs of 78°F and lows of 72°F, with about 19 rainy days per month. Expect high tourist crowds and above average accommodation rates. The overall travel score averages 52/100, with February being the strongest month of the season at 62/100.

Crowd and cost data estimated from regional travel patterns for this destination.

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Frequently Asked Questions

What is the best month to visit Koh Samui?
The best month to visit Koh Samui is March, with an overall travel score of 73/100. Expect average highs of 82°F, about 13 rainy days, and moderate tourist crowds.
Is Koh Samui expensive in summer?
Summer prices in Koh Samui are relatively moderate, averaging 87% of the annual rate. The most affordable month is September.
What is the weather like in Koh Samui in December?
December in Koh Samui has average highs of 78°F and lows of 72°F, with approximately 22 rainy days and 11.4 hours of daylight. The overall travel score for December is 43/100.
When is the cheapest time to visit Koh Samui?
The most affordable time to visit Koh Samui is September, when accommodation prices are at their lowest. Tourist crowds are moderate in September, making it a good option if you prefer fewer tourists. The least favorable month overall is December (score: 43/100).

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