Thailand · Gulf Islands
Koh Samui
Thailand's most complete beach island: international flights, world-class spas and quiet boutique bays on one coast, all-night Chaweng on the other.
Koh Samui is Thailand's coconut island turned resort heavyweight: the country's second largest, ringed by a single road and edged with long sweeps of sand. Chaweng and Lamai carry the beach clubs, the nightlife and most of the hotel beds, while the north coast keeps calmer bays, an old teak shophouse village and the gilded Big Buddha above Bang Rak. Behind the beaches the interior is jungle, waterfalls and coconut plantation, and the island has grown into Thailand's main address for spa and detox retreats.
Suggested stay
4–7 days
Language
Thai
Currency
THB
Timezone
UTC+7
Why you'll love Koh Samui
The beaches Chaweng's long white curve for beach clubs and noise, Lamai for a rougher shore and cheaper rooms, and a string of shallow, calm bays across the north.
Wellness The island is Thailand's spa and detox capital, with hillside retreats, yoga schools and fasting programmes running quietly above the resort strips.
Temples and jungle Gilded Buddhas above the north shore, a mummified monk still seated in his robes, and waterfalls and viewpoints in the coconut-covered interior.
Island hopping The best boat access in the Gulf, with a limestone marine park, Koh Phangan's bays and Koh Tao's dive sites all within a morning.
Best time to visit
Jan-Apr
Drying out · 29-32° days
9.537° N, 99.936° E
UTC+7 · Asia/Bangkok
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Weather & when to go to Koh Samui
Month by month: typical highs and lows, rainfall and rain days.
✓ Best Jan-Apr
Conditions Jan Drying out · Feb Driest month · Mar Dry & warm · Apr Warm & calm · May Some rain · Jun-Jul Brief showers · Aug Some rain · Sep Rainy spells · Oct Monsoon · Nov Monsoon peak · Dec Heavy rain
Watch for Apr-Jun, Oct-Dec cyclones & hurricanes risk · Oct-Dec monsoon flooding risk
Cards tinted by verified verdict · big number = typical daily high, small = low · hover for conditions
When to avoid Koh Samui
October to December is the wet season here, when the northeast monsoon lands on the Gulf coast and November brings the heaviest rain and roughest seas of the year - the stretch when marine-park and island-hopping boats are most often cancelled. Samui's calendar runs opposite to Phuket's, so the Andaman coast is usually dry when Samui is not.
Top things to do in Koh Samui
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Big Buddha (Wat Phra Yai) - the gilded landmark above Bang Rak
culture arts history 👍 PopularA twelve-metre seated Buddha in gold, raised on a causeway islet off the northeast corner and visible to planes on approach. A naga staircase climbs to the terrace, with amulet stalls and food shops below and views back along the north coast.
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Chaweng Beach - the island's long white main event
nightlife music scenic 👍 PopularSix kilometres of pale sand on the east coast, shallow and swimmable at the northern end, busier and shelved more steeply in the middle. Behind it runs the strip: beach clubs, malls, massage shops and bars that stay open long after the rest of the island has gone quiet.
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Ang Thong National Marine Park - a day among forty limestone islands
nature wildlife adventure scenic ⭐ Highly recommendedAn archipelago of jungle-topped karst northwest of Samui, protected since the 1980s. Boats stop for snorkelling and kayaking, a hard climb to the viewpoint above Koh Wua Talap, and the emerald saltwater lake sunk inside Koh Mae Koh. Trips run from the west and north piers and pause in the roughest months.
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Samui's spa and detox retreats - the island's quiet second industry
wellness ⭐ Highly recommendedHillside retreats above the coast run fasting and cleanse programmes, Thai massage training, yoga courses and long wellness stays, and almost every resort has a treatment pavilion. It is the reason a lot of repeat visitors choose Samui over the Andaman islands.
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Hin Ta and Hin Yai - Lamai's grandfather and grandmother rocks
scenic culture arts 👍 PopularWeathered granite boulders at the south end of Lamai that happen to look unmistakably like human genitals, with a folk tale about a drowned elderly couple attached. Silly, brief and beloved; the rock shelf and the surf around it are the better reason to walk down.
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Wat Plai Laem - the eighteen-armed Guanyin on the lake
culture artsA white Chinese-Thai temple compound built out over a lake near the airport, centred on a huge many-armed image of the goddess of mercy and a fat laughing Buddha. Bright, modern and photogenic, and quieter than the Big Buddha a few minutes up the road.
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Fisherman's Village, Bophut - old teak shophouses and the Friday walking street
food shopping historyA short strip of Chinese-Thai shophouses on the north coast, saved rather than flattened and now full of restaurants, bars and boutiques opening straight onto the sand. The street closes to traffic one evening a week for a market that fills the whole village.
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Na Muang Waterfalls - the interior's two cascades
nature wildlife adventureNa Muang 1 drops into a pool a short walk from the road and is easy with children; Na Muang 2 is taller and needs a steep, slippery climb through jungle. Both run hardest at the end of the wet season and can be a trickle in the driest months.
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Wat Khunaram - the mummified monk of Koh Samui
culture arts historyLuang Pho Daeng, a revered local monk who died meditating in the 1970s, sits preserved in a glass case in sunglasses, his body barely decayed. It is a genuinely odd stop on the south ring road and taken very seriously by Thai visitors.
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Secret Buddha Garden - stone figures in the hill jungle
culture arts off beaten pathA hillside orchard high in the interior that a local fruit farmer filled with statues of deities, animals and villagers from the 1970s onward. The reward is as much the drive: a steep, rough track best taken in a proper four-wheel drive or on a tour.
Best areas to stay in Koh Samui
$ Budget $$ Mid-range $$$ Premium
Bophut and Fisherman's Village
Character and walkability $$Old teak shophouses on a calm north beach
Explore hotels in Bophut and Fisherman's Village →
Chaweng
First-time visitors $$Long white beach, malls and late bars
Explore hotels in Chaweng →
Lamai
Beach on a budget $Second-busiest beach, rougher and cheaper
Explore hotels in Lamai →
Choeng Mon
Families and couples $$$Sheltered northeast cove, resort-quiet
Explore hotels in Choeng Mon →
Maenam
Slow and low-key $Long quiet north beach, low-key village
Explore hotels in Maenam →
Live nightly prices from Booking.com, Agoda and others, centred on Koh Samui
Getting to & around Koh Samui
Getting there
Fly into Samui (USM) in the island's northeast corner, a short transfer from the north-coast beaches and Chaweng
Flight
Samui International Airport (USM)
An open-sided garden terminal near Bophut, built and still owned by Bangkok Airways, with buggies instead of jetways. Hotel minivans, shared shuttles and taxis reach Choeng Mon and Bophut in about ten minutes, Chaweng in fifteen, and Lamai or Maenam in half an hour.
Ferry
Nathon, Lipa Noi and Bang Rak piers
Vehicle ferries cross from Donsak on the mainland near Surat Thani in around an hour and a half, and fast catamarans link Koh Phangan, Koh Tao and Chumphon. Crossings are the first thing cancelled in rough weather.
Train
Surat Thani (Phun Phin) station
Overnight sleepers run down from Bangkok, then a connecting bus to Donsak pier and the ferry across. Slow, cheap and a genuinely pleasant way to arrive.
Coach
Nathon pier
Joint bus-and-ferry tickets from Bangkok travel overnight and land you on the island the next morning. Long, but the through ticket removes the connections.
Getting around
Songthaew
Converted pickups run the ring road as shared taxis in daylight; flag one down and agree the fare before boarding.
TBC
Taxi and ride apps
Meters are widely ignored on Samui, so settle the price first or book through an app.
TBC
Scooter hire
Cheap and everywhere, but the ring road is fast and hilly and the island has a bad crash record; helmet and a licence that actually covers you.
TBC
Hire car
The ring road is a straightforward loop of about fifty kilometres, and a car makes the waterfalls and west coast easy.
TBC
Walking
Fine within Chaweng, Lamai and Fisherman's Village; useless between them.
Free
Day trips from Koh Samui
Ang Thong National Marine Park
Full dayLimestone marine park
Forty-odd jungle-topped karst islands with snorkelling stops, kayaking through arches and a steep climb to the viewpoint over the whole archipelago. The emerald inland lake on Koh Mae Koh is the image everyone comes back with.
Getting there
ferry | tour
About 1.5 hr by speedboat or 2 hr by big boat from the west or north piers
Koh Phangan
Full dayNeighbouring island
Ten times quieter than its reputation away from Haad Rin, where the monthly full moon party fills the sand. The north and east hold Bottle Beach, Thong Nai Pan and jungle waterfalls, plus a long-running yoga and retreat scene at Sri Thanu.
Getting there
ferry
20-40 min by catamaran from Bang Rak or Maenam
Koh Tao
1-2 daysDive and snorkel island
One of the world's busiest places to learn to dive, with warm shallow reefs and the twin-lobed Koh Nang Yuan just offshore. Doable in a long day, but the boat times mean a night on the island is far better.
Getting there
ferry
About 1.5-2 hr by catamaran via Koh Phangan
Sail Rock (Hin Bai)
Full dayPinnacle dive site
The Gulf's signature dive: a granite pinnacle rising from open water with a vertical chimney you can swim up through, big schools of barracuda and trevally, and whale sharks passing most often around March to May and September to October.
Getting there
ferry | tour
About 1.5 hr by dive boat towards Koh Phangan
Khao Sok National Park
1-2 daysRainforest and lake
Very old rainforest under limestone towers on the mainland, with floating raft houses on Cheow Lan lake, caves and gibbons at dawn. A rushed day trip at best; almost everyone who goes stays the night on the water.
Getting there
ferry | bus | car
Ferry to Donsak then about 2 hr by road
A little history of Koh Samui
Samui was a coconut island long before it was a beach one. Hainanese and southern Chinese traders settled its bays from the 1800s and planted the interior with coconut palms, and for a century the island shipped copra and dried fish to Bangkok by boat while staying almost untouched by the mainland. There was no road around it until the 1970s: villages on opposite coasts dealt with each other by sea, and the first backpackers arrived on the coconut boats from Surat Thani to camp at Chaweng and Lamai.
The ring road and then the airport changed everything. Bangkok Airways built and still owns the runway that opened in 1989, putting the island an hour from Bangkok, and bungalows gave way to resorts through the 1990s. The 2000s added luxury villas and spa retreats along the north and west coasts and turned Samui into a honeymoon and wellness destination. Coconuts still grow behind the beaches, Nathon is still the administrative town and port, but tourism now runs the island - along with the water and waste pressures that came with it.
Hainanese and southern Chinese settlers establish coconut plantations and trade the crop to Bangkok by boat
Copra and dried fish are the island's whole economy; Nathon grows as the port and administrative town
A paved ring road finally links the beaches, and the first backpackers arrive on the coconut boats to camp at Chaweng and Lamai
Luang Pho Daeng dies meditating at Wat Khunaram; his preserved body is still displayed there
Ang Thong is gazetted as a national marine park, protecting the karst archipelago northwest of the island
Bangkok Airways opens the airport it built and still owns, putting Samui an hour from Bangkok
Beach bungalows give way to resorts along Chaweng and Lamai and the island turns fully to tourism
Luxury villas and hillside spa retreats spread across the north and west coasts and the wellness industry takes hold
Building and visitor numbers outrun the island's water supply and waste handling, a recurring local issue
Know before you go
Payment
Cash preferred
English
Widely spoken
Wifi
Reliable
Power
Type A / B / C / O
230 V, 50 Hz
Dialing
+66
Cyclones & hurricanes risk in this window; check current conditions before you go.
Monsoon flooding risk in this window; check current conditions before you go.
The months our climate read flags to avoid: the wettest, lowest-rated weather of the year.
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FAQs about Koh Samui
▸ When is the best time to visit Koh Samui?
January to April is the pick, dry and hot with the calmest seas for boat trips. October to December is the wet season, with November the worst of it. The middle of the year sits between the two, hot and humid with passing showers, and much drier than Phuket at the same time.
▸ How many days do you need in Koh Samui?
Four or five days covers a beach base, the Big Buddha and temple loop, the waterfalls and one boat trip. A week works better if you want Ang Thong plus a night on Koh Phangan or Koh Tao, or if you are here for a retreat rather than sightseeing.
▸ Koh Samui, Koh Phangan or Koh Tao?
Samui for comfort: direct flights, the widest range of hotels, proper restaurants and the spa scene. Phangan for the full moon party and a quieter, scruffier east coast. Tao for diving, cheap and social. They are close enough that many people take two of the three in one trip.
▸ How do you get to Koh Samui from Bangkok?
Flying is quickest, about an hour, but the airport is privately owned and the route is dominated by one airline, so fares run well above the mainland alternatives. The overnight train or bus to Surat Thani plus the ferry from Donsak is far cheaper and takes most of a day.
▸ Is Koh Samui good for families?
Yes. The northern bays such as Choeng Mon, Bophut and Maenam are shallow and calm, resorts are geared to children, and airport transfers are short. Chaweng and Lamai are the noisier choices, with bar strips right behind the sand that can run late.
▸ Should you hire a scooter on Koh Samui?
Only if you genuinely ride. The ring road carries fast traffic, has steep and slippery sections, and Samui has a poor record for scooter injuries; travel insurance often will not pay without the right licence. Songthaews, taxis and a hire car cover the island fine.
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