Koh Samui
Lamai Beach, Koh Samui
Koh Samui's second beach and its calmer one: four kilometres of sand, a shorter strip, and more room per person than Chaweng. It is also the only beach on the island with a marine grid cell to itself.
Lamai is Koh Samui’s second beach and, for a good number of returning visitors, its better one. Four kilometres of east-facing sand about twenty minutes south of Chaweng, with a shorter strip behind it, more room per person on it, and prices a notch below.
It is also the only beach on the island this site can measure on its own, which turns out to be the most interesting thing about it.
The only Samui beach measured alone
The marine model we use works on a grid of about five kilometres. On Koh Samui that puts Chaweng, Bophut, Maenam, Choeng Mon and Silver Beach all in one cell, sharing a single series between them: whatever the model says about one, it says about all five.
Lamai is far enough south to fall in a cell of its own, so its figures describe Lamai and nothing else. That makes it the only beach on the island where a wave number means what it appears to mean.
What it says is that Lamai runs two to five hundredths of a metre above Chaweng in every month of the year. That is a consistent difference and it is smaller than a five-kilometre grid can honestly resolve. The two beaches have the same sea. The number is worth having because it is unshared, not because it is different.
The sea and the sky are out of phase
- Rainfall, millimetres per month
- Phuket, for comparison
Driest is February at 41mm over 7 rain days, wettest is November at 313mm over 23 rain days. Against Phuket, Koh Samui is wetter in 4 months of the twelve, and the largest gap is in November.
Lamai is calmest in October, at 0.25 metres, and October is Koh Samui’s second-wettest month at 270mm. It is roughest in December at 0.66 and February at 0.63, in the middle of the dry season.
The northeast monsoon does this. It comes down the Gulf from November into January and Lamai faces straight into it, so the bright dry weeks are the ones with a shore break. The southwest monsoon that closes the Andaman coast from May to September arrives here across the peninsula and flattens the water instead.
June is the month both numbers agree on: 85mm and 0.32 metres. April and May are close. That is the northern summer, and it is precisely when Phuket and Krabi are unusable, which is the argument for this coast in one line.
Lamai or Chaweng
Lamai for space, for a quieter evening, for a slightly cheaper week, and for the Sunday night market. Chaweng for choice: more restaurants, more nightlife, more shops, and the airport twenty minutes closer.
The sea is not the deciding factor and this page has the numbers to say so. What decides it is how much you want within walking distance.
The rocks, and the market
At the southern end of the beach the sand runs out into granite, and among the boulders are Hin Ta and Hin Yai, the Grandfather and Grandmother rocks, which are shaped exactly as their names promise and are Samui’s most photographed natural feature by some distance. They are free, they take ten minutes, and the walkway to them is lined with stalls.
The Sunday night market on the main street is the best on the island: food rather than souvenirs, and busy enough that people drive over from Chaweng for it.
Where Lamai sits among the rest
All eight beaches side by side, and the tide caveat that catches people out on the north coast, are on Koh Samui’s beaches. The island’s month-by-month figures are on the weather page, and where to base yourself is on where to stay.
Lamai Beach, Koh Samui FAQs
Is Lamai better than Chaweng?+
For space and quiet, yes; for choice, no. Lamai has more sand per person, a shorter and less relentless strip, and prices a notch below. Chaweng has more restaurants, more nightlife and better shopping. The sea is effectively identical: they face the same way on the same coast.
When is the sea calmest at Lamai?+
October, at 0.25 metres of mean daily-maximum wave height, which is also Koh Samui's second-wettest month. The roughest is December at 0.66 and February at 0.63, in the dry season. The sea and the rain on this coast are out of phase and Lamai is no exception.
What is the best month for Lamai?+
June, at 85mm of rain and 0.32 metres of sea, with April and May close behind. That is the northern summer, when the Andaman coast is at its worst, which is the whole reason the Gulf exists as an alternative.
Is Lamai good for swimming?+
Most of the year, and it has the same seasonal catch as the rest of this coast: the shore break arrives with the dry season rather than the wet one. There are also rocks at the southern end, which is where the sand gives way to the Grandfather and Grandmother formations.
What is there to do at Lamai?+
A night market on Sunday that is the best on the island, the Hin Ta and Hin Yai rocks at the southern end, and the beach. Beyond that Lamai is a place to be rather than a place to work through, which is most of the point of choosing it over Chaweng.
How warm is the sea at Lamai?+
Between 28.6C in January and 31.9C in May, from four years of marine reanalysis at Lamai's own coordinates. Lamai is the only beach on Koh Samui that gets its own cell in that model rather than sharing one.