December in Thailand marks the start of the best six months of the year. But only on one side of the country. On the other side, it's still pouring, storming, and the news is filled with storm warnings. Mix up the coasts in December, and you can easily ruin your vacation.
High season in Thailand doesn't start everywhere at once. The Andaman coast (west) dries out by November and is already shining by December. The Gulf of Thailand (east) runs on a different schedule — and December is exactly when Samui gets its share of storms. Knowing this difference is the key to choosing correctly.
Phuket: December at Its Best
December on Phuket is one of the two best months (tied with January). The monsoon has left, the sea has calmed, and the water is crystal clear.
Air at +29–31°C, water at +28–29°C. Rain is virtually nonexistent — one or two brief showers all month. Winds are light, no waves. All beaches operate without restriction: Karon, Kata, Patong, Nai Harn, Bang Tao, Kamala — the red flags are down and the lifeguards are relaxed.
Since mid-November, the Similan Islands — the country's top dive spot — have been open. In December, underwater visibility reaches 25–30 meters, currents minimal. Ideal conditions for divers and snorkelers.
The flip side is prices. December kicks off a price rally that peaks at New Year's. Hotels in the first half of the month run 30–40% more expensive than November. In the second half, 50–100%. Book for the Christmas and New Year dates at least 3–4 months ahead.
Krabi and Koh Lanta: Same Climate, Fewer People
Krabi, Ao Nang, Railay, Koh Phi Phi, Koh Lanta — this entire cluster follows Phuket's schedule. December is dry, sunny, the sea calm.
The advantage over Phuket is less mass tourism. Koh Lanta in December is a quiet island with long beaches and the feeling that high season hasn't fully kicked in. Railay offers cliffs, lagoons, kayaking. Koh Phi Phi is louder, but December water here is so clear you can see fish from the boat.
Koh Lipe — a small island to the south, near the Malaysian border. It takes longer to reach, but in December it's one of the most beautiful beaches in the Andaman Sea: white sand, turquoise water, coral right offshore.
Pattaya: Reliable and Predictable
Pattaya in December is dry season in the fullest sense. No rain, air at +28–31°C, water at +27–28°C. The Gulf of Thailand sea is calmer than the Andaman coast at any time of year — waves are rare.
For anyone wanting warm sea, affordable prices, and a short transfer from Bangkok (two hours), Pattaya is a solid option. Infrastructure is fully developed: hotels, restaurants, nightlife, entertainment. The beaches aren't Thailand's finest, but Koh Larn and Koh Samet, a half-hour boat ride away, make up for it.
Bangkok: December for City Sightseeing
If your itinerary includes Bangkok, December is ideal. Cool dry season: +25–30°C, humidity at its lowest. Walking through temples, markets, and canals — without the summer mugginess and without the risk of getting soaked.
The Grand Palace, Wat Pho, Wat Arun — no lines, no sauna feeling. Chatuchak, the floating markets, Chinatown — all running and thriving. An evening on the Chao Phraya riverside promenade is one of the city's best experiences.
Tip: schedule Bangkok at the start of your trip — two or three days in the capital, then a flight to the coast. Domestic flights Bangkok–Phuket start at 1,500–2,500 baht and take an hour and a half.
Chiang Mai and the North: Cool and Clear
December in the north is the best time of year. Air at +20–25°C during the day, +10–15°C at night — that's cold by Thai standards, and locals wear jackets. For a Russian traveler, it's heavenly coolness.
Skies are clear (unlike March–April, when the north gets choked with smoke from agricultural burning), mountains are sharply visible, and rice terraces glow in dry golden tones. Chiang Mai's temples, the night market, a trip to Pai — all operating fully.
The headline event is the Yi Peng lantern festival. Usually held in November, though the dates shift and sometimes stretch into early December. Thousands of paper lanterns rising into the night sky — one of Thailand's most photographed scenes.
Why Samui in December Is a Mistake
Samui, Koh Phangan, Koh Tao — the eastern coast, and December here is not yet in season. The northeast monsoon brings rain precisely from October through December — right when the western coast is already shining.
The numbers speak for themselves: Samui gets 445 mm of rain in November, 265 mm in December. For comparison, Phuket in December gets under 30 mm. A nearly tenfold difference.
The sea is unsettled, waves build on the eastern beaches, and excursions to neighboring islands get canceled. Conditions improve by the second half of December, but there are no guarantees. January is the first reliably good month for Samui.
Every December, dozens of tourists book Samui after reading that "Thailand's high season starts in November." That's true — but not for Samui. Remember: December is Phuket and Krabi. Samui starts in January.
How to Save Money in December
December is expensive — but not uniformly so.
- The first two weeks are 20–30% cheaper than the last. The main price jump hits around December 20–25, when Christmas and pre-New Year arrivals begin. If your schedule allows, December 1–15 delivers the same weather for a noticeably smaller budget.
- Krabi and Koh Lanta are cheaper than Phuket for the same weather. The hotel price difference runs 15–25%. Beaches are just as good; the atmosphere is calmer.
- Domestic flights. Bangkok–Krabi or Bangkok–Phuket on budget airlines start from 1,000 baht one-way if booked in advance — cheaper than a taxi from the airport.
- Street food. Thai cuisine at markets and food carts costs the same year-round — 40–80 baht per dish. Restaurant prices climb in season; street prices don't.
Which Resort to Choose in December
- Want a world-class beach — Phuket. Karon and Kata for families, Patong for nightlife, Nai Harn for quiet.
- Want quieter and cheaper — Krabi, Koh Lanta, Koh Lipe. Same weather, fewer people.
- Want city plus sea — two days in Bangkok, then a flight to Phuket or Krabi.
- Want mountains and temples — Chiang Mai. Coolness, clear skies, atmosphere.
- Don't want to gamble — any resort on the Andaman coast, or Pattaya.
The one "no" in December: Samui. Better to wait until January and get the same island — with sunshine instead of constant rain.
