Things to Do in Koh Tao in December

Q: Is Koh Tao safe for solo travellers in December?

Koh Tao rates 7.6 out of 10 for solo safety (see /research/solo-safety/). The main December risks are practical: slippery hill roads for scooter riders and heavy drinking on the busy late-month beach nights. Ride carefully, and don't lose sight of your drink on Sairee.

VerdictFair
Ranked#9 of 12
PricesExpensive

Stay in Koh Tao in December

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December on Koh Tao sits at the tail end of the Gulf of Thailand's northeast monsoon, and that is the one fact that shapes the whole month. November is the island's wettest month by a wide margin; December is the recovery. The first two weeks can still bring grey mornings, choppy seas off Tanote Bay, and the occasional cancelled Lomprayah or Songserm crossing from Chumphon, but by the third week the rain usually tapers off, the swell drops, and the water off Sairee Beach goes from murky green back toward blue.

Temperatures barely move. Days top out around 27°C (81°F) and nights hold near 25.4°C (78°F), so the air stays warm and sticky whether it rains or not. The real variable is the sea: divers booking an Open Water course in early December might lose a day or two to weather, and visibility at Chumphon Pinnacle tends to be poor after heavy rain.

Then Christmas arrives and the island changes character. Rooms in Sairee and Mae Haad fill from around 20 December, prices climb toward their yearly high, and the New Year's Eve crowd lands. So there are two Decembers here: early in the month is cheap-ish, quiet, and a gamble on the weather, while late December is drier, busy, and expensive.

Why visit in December

From about mid-December the northeast monsoon usually weakens, so rain falls on fewer afternoons and the seas around Koh Nang Yuan settle down.
Early December dive schools in Sairee and Chalok Baan Kao run smaller Open Water groups, often 2 to 4 students per instructor rather than the 6 to 8 you might see in March or July.
The west coast, Sairee and Mae Haad, sits in the lee of the northeast wind, so sunset swims and west-side dive sites stay usable while the east coast churns.
After a month of rain the hills behind Mae Haad are deep green, and the viewpoint trails have clearer air than in the hazy months of March and April.

Worth knowing

Rough seas in the first half of the month can cancel or delay the high-speed catamarans from Chumphon, and even the Koh Samui and Koh Phangan legs get bumpy enough to make people sick.
Underwater visibility at Chumphon Pinnacle and Sail Rock often drops to 5 to 10 m (16 to 33 ft) after heavy rain, compared with 20 m (66 ft) or more in the calm months.
East-coast bays like Tanote Bay and Ao Leuk take the swell head-on, so snorkelling there is often off the table until late in the month.
From roughly 20 December to 2 January, room rates rise toward the annual peak and the good sea-view bungalows in Sairee sell out weeks ahead.

Best for

Think twice if

Weather measured 27° / 25°C 135mm rain · 11 rainy days · 76% humidity rains perceptibly ~2h/day · 77% of mornings dry

Crowds high

Pack Quick-dry shorts and linen shirts, a packable rain shell, reef-safe sunscreen, a dry bag for boat days and one light long-sleeve layer for air-conditioned ferries and windy evening boat rides.

December brings around 135 mm (5.3 in) of rain across roughly 11 wet days, down sharply from November's deluge. Showers tend to come in bursts, often a heavy hour in the afternoon or overnight, leaving the rest of the day warm and hazy. Humidity sits at about 76%, so clothes dry slowly and the air carries a smell of wet earth and frangipani after each downpour. The northeast wind matters more than the rain: it pushes waves into the east coast and churns the channel toward Chumphon, while the west side usually stays calmer. Sea temperature stays around 28°C (82°F), warm enough to dive in a 3 mm shorty.

Seasonal caution

Northeast monsoon swell can suspend ferry services between Chumphon, Koh Tao and Koh Phangan for 1 to 2 days at a time in early December, so build a buffer day into your schedule before any onward flight from Samui or Chumphon.

Year-round climate

Averages from the last 5 years.

Monthly climate averages for Koh Tao
Month	Avg high (°C)	Avg low (°C)	Rainfall (mm)
Jan	27	25	20
Feb	27	25	76
Mar	28	26	33
Apr	29	27	80
May	29	27	189
Jun	29	27	120
Jul	29	26	172
Aug	28	26	145
Sep	28	26	192
Oct	28	25	275
Nov	28	25	336
Dec	27	25	135

Holidays and festivals in December

Public holidays

King Bhumibol's Birthday / Father's Day(วันพ่อแห่งชาติ)5 December 2026
Constitution Day(วันรัฐธรรมนูญ)10 December 2026
New Year's Eve(วันสิ้นปี)31 December 2026

Headline events

Citywide Free

New Year's Eve on Sairee Beach

31 December into the early hours of 1 January

Koh Tao's biggest night of the year. The 1.7 km (1 mile) stretch of Sairee Beach becomes one long party, with fire-dancers, DJ sets spilling onto the sand, sky lanterns and fireworks over the water at midnight. Plenty of visitors plan their whole December trip around it, and it is the reason late-month rooms sell out.

#kohtao

Best things to do in December

PADI Open Water course in early December

diving

The Open Water course takes 3.5 to 4 days, beginning with confined-water skills and finishing with 4 open-water dives at sites like Japanese Gardens and White Rock. Koh Tao certifies more divers each year than almost anywhere else on earth.

The first 2 weeks of December fall between the November lull and the Christmas rush, so group sizes stay small and schools will usually shift a rained-out day without fuss.

Booking tipBook 3 to 5 days ahead for the first half of the month. For Christmas week, reserve at least 3 weeks out.

West-side diving at Twins and Japanese Gardens

diving

These sheltered sites off Koh Nang Yuan and Sairee are shallow, 5 to 18 m (16 to 59 ft), with hard coral, nudibranchs, blue-spotted stingrays and schools of yellowtail barracuda.

The northeast wind keeps the far pinnacles choppy in December, so dive schools lean on these protected west-side sites, which hold decent visibility even after rain.

Booking tipAsk for a morning boat. Afternoon squalls tend to roll in after 2pm in early December.

Hiking to John-Suwan Viewpoint

hiking

It's a steep 15-minute scramble over granite boulders above Chalok Baan Kao, and from the top you look across two bays at once, Shark Bay on one side and Chalok on the other.

After a month of monsoon rain the jungle is dense and green, and the rain-cleared air in December gives sharper views than the dry-season haze of April.

Booking tipThe rocks stay slick for an hour or two after a shower. Wear shoes with grip, not flip-flops.

Sunset at Sairee Beach

beach

Sairee faces due west, and the sun drops behind Koh Nang Yuan's silhouette. Low tide exposes rock pools at the northern end near the Nang Yuan ferry point.

December cloud cover tends to break up in the late afternoon, and the scattered cloud left over from the monsoon makes for the most dramatic sunsets of the year.

Day trip to Koh Nang Yuan

island

Koh Nang Yuan is three small islands linked by a white sandbar, 10 minutes by longtail from Sairee, and a viewpoint on the southern island looks straight down the sandbar.

The channel calms down in late December and the sandbar crowds thin out compared to the dry-season high of July and August, though the entry and plastic-bottle rules still apply.

Booking tipTake a longtail from the north end of Sairee before 9am and you'll beat the day-trip speedboats from Samui.

Rainy-afternoon Muay Thai class in Mae Haad

fitness

The small open-sided gyms near Mae Haad run 90-minute beginner classes with pad work, clinch drills, and plenty of sweat.

When a December squall shuts the dive boats down, a covered gym session is one of the few good ways to spend an afternoon on an island built around the water.

What to eat in December

In season: fruit

Som khiao wan (Thai sweet tangerines)
The green-skinned tangerines from northern Thailand hit their best season in December and January, and the fruit stalls near Mae Haad Pier stack them by the kilo.
Makham wan (sweet tamarind)
The new sweet tamarind harvest starts arriving in December, and the brittle brown pods, with their sticky, date-like pulp, turn up in bags at the 7-Elevens and fruit carts around Mae Haad.

On menus now

Tom yum goong
A bowl of hot, sour tom yum with lemongrass and lime leaf makes more sense on a wet December evening in Chalok Baan Kao than in the April heat, and local kitchens cook it with prawns from the Chumphon boats.

Street food peaks

Grilled squid skewers (pla muek yang)
Street carts along the Sairee walking path grill squid over charcoal every evening, and they get much busier in late December, when the holiday crowd arrives and the smoke drifts out over the beach.

Festival food

Christmas roast dinners in Sairee
Koh Tao has a large community of Western dive instructors, so plenty of Sairee restaurants serve a full roast with gravy on 25 December. Book a table by mid-month.

Regular events in December

King Bhumibol Memorial Day (Father's Day, National Day)Free

A national public holiday honouring the late King Rama IX, on which government offices and banks close and some locals wear yellow. Bars in Mae Haad may observe alcohol restrictions in the evening.

5 December

Constitution DayFree

A Thai public holiday marking the 1932 constitution: banks and the post office in Mae Haad close, but dive shops and beach bars keep running.

10 December

Christmas Day beach gatheringsFree

Koh Tao's large expat dive community turns Christmas into a beach day, so you'll see Santa hats on the boats, dive-shop barbecues, and packed restaurants in Sairee.

24-25 December

Full Moon Party at Haad Rin, Koh Phangan

The monthly all-night beach party on Koh Phangan pulls a lot of Koh Tao backpackers: a special night boat usually runs between the islands, and the December edition draws some of the biggest crowds of the year.

Follows the lunar calendar, so check the date for your year

Year-end beach clean-upsFree

Island dive centres and conservation groups run volunteer rubbish collections after the monsoon, which washes plastic onto the east-coast bays, and most wrap up with a group lunch.

Weekends through December, schedules vary by organiser

Best places this December

Sairee Beach
beach
The island's longest beach runs along the sheltered west coast: most bars and dive schools are here, the New Year's crowd gathers here, and the water stays swimmable when the east coast is closed out.
Sairee
Mae Haad Pier
transport hub
Every ferry arrives here, making it the place to check boat schedules in person on stormy mornings, and fruit stalls line the road up from the dock.
Mae Haad
John-Suwan Viewpoint
viewpoint
A granite lookout above the southern tip of the island, where the rain-greened hills are at their most vivid in December.
Chalok Baan Kao
Freedom Beach
beach
A small cove south of Chalok Baan Kao that faces south-west, so it often stays calm when northeast swell hits Tanote Bay.
Chalok Baan Kao
Koh Nang Yuan
island
Three islets joined by a sandbar off the north-west coast, with the Japanese Gardens and Twins dive sites nearby.
Sairee
Tanote Bay
bay
A boulder-framed east-coast bay where, in December, you're better off on the clifftop than in the water: the swell drives white spray over the rocks, and on a windy afternoon that makes for a good photograph.
Tanote
Chalok Baan Kao Bay
bay
A shallow, quieter bay on the south coast with a cluster of dive schools, where the water stays calmer than the east side for most of December.
Chalok Baan Kao

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Packable rain shellEarly December squalls tend to hit hard for 30 to 60 minutes and then clear, so a shell that folds into a pocket beats an umbrella when you're on a scooter. Shop
Motion-sickness tabletsTake one 30 minutes before the Chumphon catamaran: the crossing can be rough in the first half of the month, and the lower deck fills with queasy passengers. Shop
Roll-top dry bag, 10 to 20 litresLongtail rides to Koh Nang Yuan and dive boats take spray over the bow in December chop, so keep your phone and passport sealed. Shop
3 mm shorty wetsuit or rash guardThe water is warm, but a cloudy, windy December surface interval will chill you back on the boat after 3 dives in a day. Shop
Reef-safe mineral sunscreenThe UV index stays high through cloud cover, and Koh Nang Yuan checks for and restricts products that damage its reef. Shop
Grippy sandals or trail shoesThe concrete hills between Mae Haad and Chalok Baan Kao and the boulder paths to the viewpoints stay slick after the frequent December rain. Shop
Light long-sleeve shirtFerry cabins run the air conditioning hard, and the evening wind on the Sairee beachfront can feel cool after a rainy day. Shop
Printed or offline copy of your ferry bookingMobile signal on the pier can drop in bad weather, and staff rebooking cancelled boats will often ask to see the original ticket.

Insider tips

If the forecast shows northeast wind above 20 knots, ask your dive school to switch you to the Twins and White Rock sites. Most will do it without prompting, but confirm the plan the night before.
The overnight boat from Chumphon is slower but tends to run when the fast catamarans cancel, getting you onto the island in time for the next morning's dives.
Book New Year's accommodation in Chalok Baan Kao or Mae Haad rather than Sairee. You'll sleep better, the rates are lower, and a taxi to the party is a 10-minute ride.
Dive schools often start filling Christmas-week courses in November, but many hold back a few spots for walk-ins. Ask at 5pm, when new schedules are drawn up.
Shark Bay's resident blacktip reef sharks are hard to find when the east side is choppy, so save that snorkel for a calm morning in the last week of the month.

Avoid these mistakes

Booking a same-day connection from the Koh Tao ferry to a flight out of Samui or Bangkok in early December, when one cancelled sailing can cost you the flight.
Arriving on 30 December without a room booked, expecting to find a bungalow on the beach: Sairee is often full by then, and the walk-in rates that remain are well above the pre-Christmas level.
Renting a scooter to ride the steep dirt roads to Tanote Bay or Ao Leuk after a rainy night, when the red clay turns slick and the island clinics see a wave of road-rash injuries.
Signing up for an early-December snorkel trip that circles the whole island, when the east-coast stops will likely be cut or too rough to enjoy.

Practical tips for December

Book ferries through the operator desks at Mae Haad Pier or direct with the company, and check the schedule the evening before in early December because weather cancellations are posted late. For stays across Christmas and New Year, book accommodation and any Open Water course at least 3 weeks ahead, and expect a mandatory surcharge on 31 December at beachfront resorts. Alcohol sales may be restricted on 5 December, so check with your bar before planning a big night. Banks and the post office close on the two national holidays, so withdraw cash at the ATMs in Mae Haad beforehand. Keep shoulders covered and wear a shirt when walking through Mae Haad town, even though beachwear is fine on the sand. Tipping dive instructors and boat crews at the end of a course is customary.

FAQ

Is December a good time to visit Koh Tao?

It depends which half. The first two weeks can bring rain, rough ferry crossings, and lower visibility underwater, though dive courses are quiet. From about mid-month the weather usually improves, while crowds and room prices climb toward the New Year high. Overall it ranks in the bottom half of the year for diving.

What is the weather like in Koh Tao in December?

Warm, humid, and changeable. Days rarely feel cool, and showers come as short, heavy bursts, often in the afternoon. The northeast wind makes the east coast choppy while the west side, including Sairee, stays calmer.

Is Koh Tao crowded in December?

Early December is fairly quiet, with half-empty dive boats, but from about 20 December through the first days of January the island is at or near full capacity, especially along Sairee Beach.

Do ferries to Koh Tao get cancelled in December?

Yes, sometimes. The northeast wind, when it builds, can ground the fast catamarans from Chumphon and the island-hopping boats to Koh Phangan and Koh Samui for a day or two, and early December is when this happens most. Build in a spare day before onward flights.

Is Koh Tao safe for solo travellers in December?

Koh Tao rates 7.6 out of 10 for solo safety (see the TTDI Solo-Safety Index). The main December risks are practical: slippery hill roads for scooter riders and heavy drinking on the busy late-month beach nights. Ride carefully, and don't lose sight of your drink on Sairee.