Khao Lak in December: is it a good idea?

December is the month Khao Lak shows off its best weather, and the month the region fills up the most. The two go hand in hand, and that’s exactly what you need to understand before booking your trip. Here’s our full take on this month, and on what December really changes compared to the rest of the year in Khao Lak.

Is Khao Lak worth it in December?

Yes, without a doubt, if reliable weather matters more to you than budget or quiet. December brings the best climate of the year to Khao Lak, but also, logically, the highest prices and the busiest excursions. It’s a great choice for a first trip or for diving in top conditions, less so for anyone after the cheapest or the most low-key month of the year.

Weather in Khao Lak in December

December brings the most reliable weather of the year to Khao Lak, with temperatures ranging from 22°C at night to 31°C during the day, mostly clear skies, and only around 6 rainy days over the entire month. Along with January and February, it’s one of the three driest months of the year.

Humidity drops noticeably compared to the green season, which makes the heat far more bearable. The sea stays calm and clear, around 29°C, with good underwater visibility, ideal conditions for diving and snorkeling.

The best activities to do in Khao Lak in December

December is the best month of the year for a trip to the Similan Islands, thanks to flat seas and optimal underwater visibility. It’s also the most in-demand time for this excursion, so it’s worth booking early to secure a spot on the best departures.

Phang Nga Bay is a great visit this time of year, with clear skies that really show off the karst formations. A kayaking trip on the Sok River or a day at the Khao Sok village round out the program nicely, without depending on the weather. To get a feel for local life in the evening, head to the Bang Niang Market, open Monday, Wednesday, Thursday and Saturday. And for a shorter, more low-key outing, we’re happy to recommend Khao Lak Lam Ru National Park.

December in Khao Lak’s yearly calendar

December falls within Khao Lak’s dry high season, which runs roughly from November to March. This stretch brings the best climate of the year, with minimal rain and a stable sea.

April marks a hot, humid transition before the monsoon arrives. The green season, from May to October, brings more frequent showers, nature at its lushest, and noticeably lower prices, with some excursions temporarily closing. November closes the loop: the monsoon is winding down, the Similan Islands have just reopened, and prices stay reasonable before the December price surge. We break this period down month by month in our full review of Khao Lak in November.

The holiday trap: Christmas and New Year in Khao Lak

Accommodation and excursion prices climb noticeably between December 20th and January 2nd, the most expensive and most in-demand stretch of the entire year in Khao Lak. Many hotels sell out weeks ahead for this specific window, and some popular restaurants require booking several days in advance.

Outside that two-week window, the rest of the month is still high season but without the extra pressure. Traveling in early December or just after New Year gets you the same weather with more availability and more reasonable rates.

High season at its peak: what that actually means for travelers

Traveling to Khao Lak in December means accepting bigger crowds on excursions and higher prices, in exchange for near-guaranteed good weather. Boats heading to the Similan Islands run at full capacity, the best-known dive sites get shared with more groups, and popular restaurants sometimes require booking ahead for dinner.

That said, Khao Lak stays noticeably less crowded than Phuket even at its busiest. The beaches keep their breathing room, and the vibe stays far from the saturation you can feel in Patong during the same period.

What to keep in mind before booking your trip to Khao Lak in December

Booking early is the one real must for December, unlike other months where flexibility matters more than planning ahead. Plan on at least 2 to 3 months’ notice for accommodation and standout excursions if your trip falls within the last three weeks of December. The rest of the month needs less lead time, but it’s still not one to leave to the last minute.

Who December is a good fit for

December is a great fit for divers and snorkelers after the best conditions of the year at the Similan Islands, and for travelers who want guaranteed blue skies with no weather gamble. It’s also a solid choice for a first trip to Thailand, where reliable weather matters more than absolute quiet.

It’s less of a fit for smaller budgets, who’ll find better rates in the green season or in November, and for anyone chasing quiet, uncrowded excursions above all else. We cover every strength and limitation of the destination in our full review of Khao Lak.

Our local agency advice

We recommend two strategies depending on your priority. For the most reliable weather without the holiday prices, aim for the first half of December or the first week of January, the best compromise: same climate, far less pressure on bookings. For those set on being here for Christmas or New Year, book as early as possible, ideally several months ahead, since accommodation and Similan Islands excursions fill up first.

Tell us your dates, and we’ll tell you honestly whether it’s doable and how to get the most out of your booking.

Frequently asked questions

Is the weather good in Khao Lak in December?

Yes, December brings one of the most reliable weather windows of the year, with around 6 rainy days over the whole month, temperatures between 22°C and 31°C, and a calm sea at 29°C.

Are the Similan Islands open in December?

Yes, and it’s actually one of the best months of the year for this excursion, thanks to flat seas and excellent visibility. It’s also the most in-demand time, so it’s worth booking early.

Is it better to visit in November or December?

Both months offer good weather, but December is more reliable for clear blue skies, while November stays cheaper and quieter, with the Similan Islands freshly reopened. The choice mostly comes down to whether budget or weather reliability matters more to you.

What budget should I plan for a trip to Khao Lak in December?

Prices are among the highest of the year, particularly between December 20th and January 2nd. Outside that specific window, December stays expensive but noticeably less extreme than during the two-week holiday stretch.

Do I need to book far in advance for the holiday season?

Yes, at least 2 to 3 months ahead for accommodation and standout excursions like the Similan Islands, if your trip covers the December 20th to January 2nd period.

Is December a good fit for a first trip to Thailand?

Yes, it’s actually one of the best windows for a first trip, thanks to reliable weather that leaves little room for bad surprises, as long as you’re comfortable with higher prices and busier popular excursions.