Travel
The best time to swim in Thailand
Andaman Sea vs Gulf of Thailand: when the water is clearest and calmest.
5 min read
Thailand's two coasts have opposite monsoons, so the best beach depends on the month. The water is always warm; the question is whether the sea is calm enough to swim safely.
Season by coast
- Andaman Sea (Phuket, Krabi, Similans): November–April is dry and calm, 27–29°C.
- Gulf of Thailand (Koh Samui, Koh Tao): January–August is best, 27–30°C.
- May–October: Andaman west coast sees monsoon rain and rougher seas; east coast is better.
- November: Gulf coast can be wet, while the Andaman is entering its prime season.