Best Time to Visit Koh Chang — Honest Season Guide & the Monsoon Closure for 2026

Q: When is the best time to visit Koh Chang?

November to April is the best window — dry, low rain, calm clear seas, with snorkelling and boat trips to Koh Rang running, and crucially with resorts, restaurants and dive shops all open. If you can only pick one month, choose November or February–March: the weather is excellent and you avoid the long-holiday crowds. December–January and Songkran are the peak, busiest and priciest weeks.

Q: Which month has the cheapest hotels on Koh Chang?

The May–October monsoon is the low season with the lowest prices — many resorts cut rates sharply and some close for the season. The trade-off is rain, a rough sea, and many restaurants, tours and bars being shut. If you can handle the wet and want a quiet, green island with full waterfalls, it is good value, but check directly with your accommodation that it is open. The shoulder months — November at the start of high season and May at the start of the monsoon — often give better rates than peak season while most places are still open.

Q: What are November and May like on Koh Chang?

These are the transition months. November is the start of high season: the rain is easing, the sea is settling, the island is reopening almost fully, and prices haven't spiked the way they do at New Year — a very good window. May is the start of the monsoon: there are still sunny days between showers, some trips still run and prices begin to drop, but by late May the monsoon sets in properly. Both months suit travellers who want a quieter island than peak season while it is still open, but check the forecast before planning water activities.

The short answer

The best window is November–April (the dry season)

If you can only pick one month, pick November or February–March — dry, low rain, a calm clear sea, snorkelling at Koh Rang running, and, most importantly, the resorts, restaurants, dive shops and beach bars all open. This is when White Sand Beach, Klong Prao, Kai Bae and the island's viewpoints look their best. December–January and Songkran are the peak — the busiest and priciest weeks.

The thing to know before anything else: May to October is the monsoon. Rain and a rough sea mean the snorkelling trips often stop, and many resorts, restaurants, dive shops and beach bars close or run reduced hours. Koh Chang is far quieter than Phuket or Samui in low season. The upsides are lush jungle, full waterfalls like Klong Plu, cheap rooms and few crowds; the ferry still runs but crossings are choppier — so if you go then, check directly with your accommodation that it's open.

Koh Chang's two seasons

What each part of the year actually feels like

A Gulf island has only a dry season and a wet one — each with its upsides and its trade-offs, told straight.

Koh Chang in the dry season — clear blue sea and offshore islands seen from the Kai Bae viewpoint, strong sunshine

Kai Bae viewpoint · Dry season The best

Early dry season

November – January · 24–31°C

This is Koh Chang at its finest. The rain eases off, skies are clear on most days, and the sea settles and clears — the boats to Koh Rang start running again and the resorts, restaurants and dive shops reopen after their long monsoon break. Days sit around 30–31°C, kept comfortable by the sea breeze, ideal for lying on the beach, snorkelling and island-hopping.

The trade-off: this is the start of high season, so crowds build and room rates climb, especially approaching Christmas and New Year. Late November to early December remains the sweet spot, before the New Year prices spike.

Temperature: 24–31°C (sea breeze keeps it pleasant)

Rain: Low — clear skies most days

The island: Fully open, tours and boats running

Room prices: Climbing, high over New Year

Late November to early December is the sweet spot — good weather, a settling sea and the island fully open, before New Year prices spike. Book rooms and boats 2–4 weeks ahead.

Clear seas · Late dry season The best

Late dry season

February – April · 25–33°C

Many travellers rate this the best stretch of all: the sea is at its clearest and rain is still scarce. February is comfortable; March and April warm steadily from 32 up to 33°C, with sun that's strong but tempered by the sea breeze. It's the prime window for everything on the water — snorkelling over the coral, kayaking, and boat trips to Koh Rang and the southern islands.

Watch out for Songkran (mid-April), when rooms get expensive and sell out fast and the ferries fill up — the second peak of high season. Late April starts to feel hotter and brings the first rains of the monsoon, with waves building on some days.

Temperature: 25–33°C (April noticeably hotter)

Rain: Low — first showers arrive in late April

The island: Fully open, sea at its clearest

Room prices: Spike during Songkran

Songkran in mid-April sees Koh Chang rooms sell out fast and rates rise. If you travel then, book several weeks ahead and allow time for the busy ferry queues.

Lush jungle · Early monsoon Best value · some closures

Early monsoon

May – June · 26–32°C

The south-west monsoon starts here, but the early months aren't as heavy as those that follow — there are still sunny spells between showers, with the rain mostly coming in the afternoon and evening. Snorkelling trips still go out on some days when the sea isn't too rough. The jungle turns green and Klong Plu Waterfall starts to swell. This is when room rates begin to drop noticeably.

But know that the island starts to wind down from here — some restaurants, dive shops and beach bars begin to close for the season. Visitor numbers fall and the beaches are quiet. If you can take afternoon rain and want a quiet island at a low price, May–June is a good window — but check with your accommodation and tour operators first that they're open and running.

Temperature: 26–32°C (humid)

Rain: Picking up — mostly afternoon and evening

The island: Some closures begin · trips on some days

Room prices: Dropping noticeably

Want a quiet, cheap island that's still open? Early May, before the monsoon sets in fully, is your window. Swim or take a boat trip in the morning before the afternoon rain — but check first that places are open and trips running.

Koh Chang in the peak monsoon — rough sea and rain clouds, snorkelling trips stopped and much of the island closed

Rough sea · Peak monsoon Much of the island closes

Peak monsoon / low season

July – October · 25–31°C

The wettest stretch of the year, with September–October the heaviest. The sea on the island's west coast is rough and murky, the snorkelling and island-hopping trips to Koh Rang stop running for most of the period, and this is when many resorts, restaurants, dive shops and beach bars close for the season or run reduced hours — especially the smaller beaches like the south end of White Sand and Lonely Beach. Koh Chang is far quieter than Phuket or Samui in low season; some beaches feel almost deserted.

It isn't always grim — prices are at their lowest, crowds are thin, the jungle is lush and Klong Plu Waterfall is full and at its best. Clear days bring the sea right back to beautiful. But you need a flexible plan, a spare buffer day, a daily forecast check, and above all to check with your accommodation before booking that it's open and trips are running. The ferry still crosses but the sea is choppier. After mid-October the rain starts to ease and high season opens up.

Temperature: 25–31°C (very humid)

Rain: Heaviest Sep–Oct · rough sea

The island: Much closed · trips usually stop

Room prices: Lowest · some places shut for the season

In the July–October monsoon many resorts, restaurants and dive shops close and the snorkelling trips to Koh Rang usually stop. Before booking this season, check directly with your accommodation that it's open, watch the forecast, and keep an indoor backup plan.

Month by month

Koh Chang every month at a glance

Temperature, rainfall, whether the island is open and crowd levels — in one table for easy comparison.

Month	Temperature	Rain	Crowds	Notes
January	24–31°C	Very low	High (high season)	Best weather · clear sea · island fully open · high prices
February	25–32°C	Very low	Moderate	Clear sea · ideal weather · fully open
March	26–33°C	Low	Moderate	Clearest sea · best for snorkelling
April	27–33°C	Low	High at Songkran	Hottest · Songkran crowds · first rains late month
May	27–32°C	Moderate	Low	Monsoon begins · prices easing · some closures start
June	26–31°C	Heavy	Low	Afternoon rain · cheap · trips on some days
July	26–31°C	Heavy	Low	Full monsoon · rough sea · trips usually stop
August	26–31°C	Heavy	Low	Wet · much of the island closed · waterfalls full
September	25–31°C	Heaviest	Lowest	Heaviest rain · many places shut · cheapest
October	25–31°C	Heaviest	Low	Still wet · rain eases after mid-month
November	25–31°C	Low–moderate	Moderate	High season begins · island reopening · clearly improving
December	24–30°C	Very low	High (New Year)	Clear sea · fully open · prices spike over New Year

Sea & swimming conditions

When the sea is best for swimming

The water is warm year-round, but clarity, waves and whether the boats run all shift sharply with the season — here's what to know before you get in or book a trip.

Nov
Apr

Dry season — clear sea, gentle waves, best for snorkelling

November–April · the prime window for the water

The sea is at its calmest and clearest — you can see the coral well around Koh Rang and the southern islands, making it ideal for snorkelling, scuba diving, kayaking and island-hopping. The water is comfortably warm. The west-coast beaches — White Sand, Klong Prao and Kai Bae — have gentle waves, and the tour boats go out almost every day. Use our snorkelling and island-hopping guide and the Koh Chang beaches guide to pick a beach and a trip.

May
Jun

Early monsoon — still swimmable, trips less reliable

May–June · swim in the morning before afternoon rain

The sea is still swimmable on clear days, but waves grow stronger than in the dry season and the water turns murky on some days. Mornings are usually clear — the best part of the day to get in, ahead of the afternoon rain. Snorkelling trips to Koh Rang become less reliable: some days they run, some days they're cancelled because of the swell. If you're planning a boat trip this season, keep a spare day and book something flexible you can move.

Jul
Oct

Peak monsoon — trips usually stop, mind the waves and currents

July–October · rough sea, snorkelling trips usually stop

The west-coast sea is rough with strong currents, and the snorkelling and island-hopping trips to Koh Rang stop running for most of the period. On the roughest days even swimming off the beach isn't safe — always check the warning flags and ask locally before getting in; a red flag means no swimming. What still works is the inland side of the island: Klong Plu Waterfall is full and beautiful, jungle walks, and kayaking in the sheltered east-coast bays.

When to avoid

The peaks that spike prices and crowds

Koh Chang has two Thai high-season peaks and a monsoon when the island closes — these are what many travellers don't realise until they've booked.

Late
Dec

Christmas – New Year

Late December–early January · the dry season's peak

The peak of high season, because the weather is at its best and it lines up with the New Year break, when Thai and international travellers head to the island all at once. Room rates are the highest of the year, the better resorts sell out fast, and the ferries are packed on holiday days with long vehicle queues for the crossing. For dry-season weather at more reasonable prices, shift to early-to-mid January once the New Year crowds clear, or aim for early November before the peak arrives — and book rooms and boats several weeks ahead.

Mid
Apr

Songkran (Thai New Year)

Around April 13–15 every year

The Songkran long weekend is Koh Chang's second high-season peak, when Thai travellers move all at once. Rooms fill fast and rates rise, and the ferries get very busy on travel days, with vehicle queues for the crossing that can run to an hour. It's the hottest part of the year, but the sea is still clear and the island fully open, with relaxed water-splashing along the beaches and villages. If you go then, book several weeks ahead, allow time for the ferry queues, and avoid travelling on the first and last days of the holiday.

Jul
Oct

Peak monsoon — much of the island closed

July–October · heavy rain, trips stopped

This isn't a crowded period, but it's the one to avoid if you want the island fully open. The rain is heaviest in September–October, the sea is rough, the snorkelling trips to Koh Rang usually stop, and many resorts, restaurants, dive shops and beach bars close for the season — some smaller beaches feel almost deserted. If you do come, check with your accommodation first that it's open, be ready for the rain, and focus on what still works — waterfalls and jungle walks — rather than the sea activities.

Packing by season

What to bring for each season

A hot, humid island means a light bag — these are the things that actually matter for Koh Chang.

Dry season

November – April

Two swimsuits — you'll be in the water daily; clear seas, gentle waves
High-SPF water-resistant sunscreen — tropical sun is fierce; choose reef-safe ☀️
Hat and sunglasses — strong sun on most days
Snorkel gear if you have it — the sea is at its clearest 🤿
Water shoes — Kai Bae and a few beaches have rocks at low tide
Cash — ATMs on the island are limited and small shops are cash-only 💵

Monsoon

May – October

Compact umbrella or light rain jacket — afternoon and evening rain is routine 🌧️
Quick-dry clothing — breathable fabrics; the humidity is high
Non-slip shoes — the waterfall path and roads get wet and slippery
Waterproof phone pouch — rain arrives fast and heavy
Insect repellent — the wet, green jungle means more mosquitoes 🦟
Check ahead that your hotel, restaurants and tours are open — many close this season

Koh Chang in every light

Koh Chang any season

Whatever month you arrive, this big jungle island always has something worth seeing.

The west-coast beach and sea of Koh Chang in the dry season

The Trat mainland ferry pier, where boats cross to Koh Chang

Koh Chang overview — green jungle mountains and offshore islands from a viewpoint

Frequently asked

FAQ · Before you book

When is the best time to visit Koh Chang?

November to April is the best window — dry, low rain, calm clear seas, with snorkelling and boat trips to Koh Rang running, and crucially with resorts, restaurants and dive shops all open. If you can only pick one month, choose November or February–March: the weather is excellent and you avoid the long-holiday crowds. December–January and Songkran are the peak, busiest and priciest weeks.

What is Koh Chang like in the May–October monsoon — is it open?

Koh Chang is genuinely seasonal. The south-west monsoon from May to October brings heavy rain and a rough sea, the snorkelling and island-hopping trips to Koh Rang often stop running, and many resorts, restaurants, dive shops and beach bars close or run reduced hours. The island is far quieter than Phuket or Samui in low season. The upsides are lush green jungle, full waterfalls like Klong Plu, cheap rooms and few crowds; the ferry still runs but crossings are choppier. Before booking this season, check directly with your accommodation that it's open and trips are running. See how to get to Koh Chang.

When should you avoid visiting Koh Chang?

If you dislike crowds and high prices, avoid the peak of high season: New Year (late December to early January) and Songkran (mid-April), when rooms are expensive and sell out fast and the ferries are packed — book several weeks ahead. If you don't want to find much of the island closed, avoid the heart of the monsoon, May to October, especially September–October when the rain is heaviest. See our Koh Chang trip budget guide.

Which month has the cheapest hotels on Koh Chang?

The May–October monsoon is the low season with the lowest prices — many resorts cut rates sharply and some close for the season. The trade-off is rain, a rough sea, and many restaurants, tours and bars being shut. If you can handle the wet and want a quiet, green island with full waterfalls, it's good value, but check directly with your accommodation that it's open. The shoulder months — November and May — often give better rates than peak season while most places are still open. Browse options in our Koh Chang & Trat hotels guide.

When should you go snorkelling at Koh Chang?

Snorkelling and island-hopping trips to Koh Rang and the southern islands run best from November to April, when the sea is calm and clear. During the May–October monsoon the sea is rough and murky, and trips often stop running or go out on only a handful of days. If you're coming mainly to snorkel, travel in the dry season and keep a spare day, because even in high season the sea is too rough for the boats to leave on some days. See the snorkelling and island-hopping guide.

What are November and May like on Koh Chang?

These are the transition months. November is the start of high season: the rain is easing, the sea is settling, the island is reopening almost fully, and prices haven't spiked the way they do at New Year — a very good window. May is the start of the monsoon: there are still sunny days between showers, some trips still run and prices begin to drop, but by late May the monsoon sets in properly. Both suit travellers who want a quieter island while it's still open, but check the forecast before planning water activities.

Koh Chang City Guide

Hotels, beaches, getting around and practical tips — all in one place

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Things to Do on Koh Chang

Beaches, viewpoint, Klong Plu Waterfall and snorkelling — all in one place

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Snorkelling & Island Hopping

Koh Rang, Koh Wai and the southern isles — the boat trips that depend on the season

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How to Get to Koh Chang

Bus or flight to Trat plus the car ferry to the island — start here

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