Best months to visit
AprilMay
November to April is the classic Koh Chang window — dry, sunny, calm sea, full operations. December-February is most reliable. March-April are hot. May-October is the wet season — many resorts close, beaches rough, jungle trails slippery and the National Park diving suspends. Always check resort opening dates before booking May-October.
Best for
Beach
November-April — White Sand Beach, Klong Prao and Kai Bae are calm, dry and warm. Sea 28-31 °C, full beach service.
Hiking
December-March — Klong Plu Waterfall, Salakphet and the central ridge trails are driest and least slippery; mid-year heavy rain makes them muddy and leech-prone.
Sightseeing
November-April — Bang Bao fishing village, Salakphet temple, snorkel trips to Koh Wai and Koh Rang most reliable.
Climate notes
- Mid-year wet season (May-October): Koh Chang sits on the EASTERN side of the Gulf, near Cambodia, and catches the SW monsoon directly. May-September averages 310-620 mm of rain per month — among the wettest in Thailand. This is closer to the Andaman timing than to Koh Samui.
- Long dry-cool window (November-April): the NE monsoon bypasses Koh Chang's east-coast position, leaving 25-90 mm/month and many of the best beach days of the year.
- Critical distinction from Koh Samui: although both are 'Gulf of Thailand' islands, Koh Chang's wet season is OPPOSITE Koh Samui's. May-October works perfectly at Samui but is the worst time for Koh Chang.
- Mountainous interior: at 744 m the central ridge generates strong orographic rainfall — the highest peaks see over 4 m/year. Trails at Klong Plu Waterfall and the deep jungle behind Lonely Beach can be muddy from May to November.
- Tropical thunderstorms: short, intense afternoon downpours during the wet season; mornings are often clear, even at peak rainfall.
- Cyclone-rare: at 12°N Koh Chang sits below the typical typhoon track; tropical depressions occasionally cross from the South China Sea via Cambodia.
Temperature (min / max °C)
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Rainy days per month
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Sunshine hours per month
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Regional notes
- White Sand Beach (NW main beach): widest sandy strip, busiest tourist area; calm in dry season, exposed in monsoon.
- Klong Prao (W central): river estuary and a quieter long beach; good family option.
- Lonely Beach (SW): backpacker hub; rougher swell during monsoon.
- Bang Bao and the south coast: sheltered fishing-village area; calm year-round, snorkel-tour pier for Koh Wai and Koh Rang.
- Klong Plu Waterfall and central jungle (200-700 m): lush, often misty, much wetter than the coast in any season.
- Mu Ko Chang National Park (offshore reefs): peak diving December-April with visibility 15-25 m; closed entirely or reduced June-September.
Frequently asked questions
When is the best time to visit Koh Chang?
November to April — the dry season. December-February has the calmest sea, lowest humidity and reliable sun. November and March are quieter shoulder months with similar weather. Many resorts close from May through October.
Why is Koh Chang's wet season different from Koh Samui's?
Geography. Koh Chang sits on the EASTERN side of the Gulf near Cambodia and catches the SW monsoon (May-October) head-on, like the Andaman side. Koh Samui sits in the southern Gulf, sheltered from the SW monsoon, and has its wet season later (October-December). Both are 'Gulf' islands but with opposite rain patterns.
Can I visit Koh Chang in July-August?
Possible but not recommended. Many resorts close, beaches are rough, jungle trails are muddy and leech-prone, and the National Park dive operations stop. The few resorts that stay open offer half-price rates but with daily storms.
Are there cyclones or typhoons at Koh Chang?
Direct typhoon hits are very rare — Koh Chang at 12°N is below the main typhoon track. Tropical depressions cross occasionally from the South China Sea via Cambodia, amplifying SW monsoon rain. Tropical Storm Pabuk (January 2019) was an unusual dry-season exception.
When is the National Park diving best at Koh Chang?
November-April. The Mu Ko Chang National Park reefs at Koh Rang and Hin Luk Bat have visibility of 15-25 m in dry season. Operations close or scale back significantly during May-October monsoon.
Is Koh Chang quieter than Koh Samui or Phuket?
Yes — Koh Chang has a less developed feel. Mountainous, jungle-covered, with smaller beach communities and a national park covering much of the interior. Family and nature-oriented travellers choose Koh Chang over the busier southern islands.
What is the water temperature at Koh Chang?
28-31 °C year-round. April-May is the peak. Most snorkellers and divers go without a wetsuit.
Andaman vs Gulf of Thailand — where does Koh Chang fit?
Geographically Koh Chang is in the Gulf, but its weather pattern matches the Andaman side: wet season May-October, dry November-April. Travellers planning around weather should treat Koh Chang as 'eastern Gulf' — different from Koh Samui and Koh Tao despite all three being 'Gulf' islands.
Climate data: Open-Meteo · 2020–2025