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When To Go · Destination Guide

Trat and the Koh Chang Archipelago

Wrecks, coral gardens, and slow-island beach days in Thailand's eastern Gulf

Updated Jan 23, 2026 • 16 sources

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When to go

Best time to visit Trat and the Koh Chang Archipelago

This corner of the Gulf of Thailand is strongly seasonal.

Best overall window

November to April

Drier weather, calmer seas for ferries and day boats, water around 28°C.

Outside that window

Rainy season and rougher sea crossings; some operators reduce schedules or cancel on wind.

Choose your trip style

Start with the overall answer, then switch only when scuba, freedive, snorkel, or topside timing changes the trip in a meaningful way.

Month-by-month planner

The overall row stays visible so you can compare it against the currently selected scope.

BestGoodTradeoffsMore variable
ScopeJanFebMarAprMayJunJulAugSepOctNovDec
Overall
Wildlife goals and seasonal highlights

These do not replace the overall planner. Use them only if a specific animal or event is driving your trip dates.

  • Waterfalls at peak flow

    Best for Topside

    Jul to Oct

    JanFebMarAprMayJunJulAugSepOctNovDec

    Rainyseason volume makes waterfall hikes on Koh Chang and Koh Kood more dramatic.

  • Songkran (Thai New Year)

    Best for Topside

    Apr

    JanFebMarAprMayJunJulAugSepOctNovDec

    April brings Thailand's famous water festival.

  • Best shot at clear-water snorkel days

    Best for Snorkel, Scuba

    Jan to Mar

    JanFebMarAprMayJunJulAugSepOctNovDec

    A run of calmseason days often delivers the clearest snorkeling around the nationalpark islands.

  • Sea turtle-friendly shallow reefs

    Best for Snorkel, Scuba, Freedive

    Nov to Apr

    JanFebMarAprMayJunJulAugSepOctNovDec

    Shallow reefs around Koh Kood and the park islands can produce turtle sightings, especially when visibility is good and crowds are lower.

Always true for this destination
  • Peak crowd and pricing usually land in late December and January.
Seasonal cautions
  • May, Oct: Transition months with mixed sunshine and showers; plan flexibility for boat schedules.
  • Jun to Sep: Rainy season and rougher sea crossings; some operators reduce schedules or cancel on wind.

Built from climate references, access rules, and destination operators. Wildlife timing and route flexibility can shift year to year.