Koh Samui's ring road circles the island past beaches that have almost nothing in common with each other. Chaweng at night is neon and noise. The south-west at sunset is one of the quietest places in Thailand. Picking the right coast matters on a Samui visit, because getting it wrong means fighting traffic to reach the version of Samui you actually wanted.
For the island overview, see our Koh Samui guide. For traveling with children, our Koh Samui with kids guide covers which beaches work best for families.
Chaweng: the big one
Chaweng is seven kilometers of white sand on the east coast and the island's center of gravity. The beach itself is beautiful, wide, soft and swimmable for most of the year. Behind it sits the busiest strip in the Gulf, with restaurants, bars, shops, clubs and traffic.
Who it suits is straightforward. First-timers who want everything within walking distance, young travelers, and families who like convenience and don't mind noise. The northern end of Chaweng is calmer than the central section; Chaweng Noi lies beyond the southern end and is another quieter option. Busy periods vary, so check your dates and the beach conditions before booking.
Lamai: Chaweng's mellower sibling
Lamai, further south on the same coast, is the second-biggest resort beach and, in our experience, the better-balanced one. The sand is golden rather than white, the bay curves between rocky headlands, and the town behind it has everything Chaweng has at about two-thirds the intensity. The famous Hin Ta and Hin Yai rock formations sit at the southern end, and the Sunday walking street market is one of the island's best evening outings.
Lamai suits couples, families and longer-stay visitors who want amenities but plan to sleep at night. The swimming is good, though the shelf drops a bit faster than at Chaweng in places.
Bophut and Fisherman's Village: the charming choice
Bophut on the north coast is a proper beach town with a swimmable, gently shelving bay, and at its heart sits Fisherman's Village, a row of old wooden Chinese shophouses turned into restaurants, boutiques and bars. On Friday nights the whole street becomes a walking market with food stalls, live music and fire performers, and it's the single most atmospheric evening on the island.
The beach is narrower and less dramatic than the east coast's, but the setting wins people over. It suits couples, families with small kids who value calm water and strollable evenings, and anyone who finds Chaweng exhausting. The nearby Bang Rak pier area, under the Big Buddha, is worth a morning visit.
Maenam: wide, flat and local
Maenam stretches along the northwest coast, broad and flat with a village feel and a mix of travelers and Thai families. The sand is coarser in patches and there are rocks at the low-tide line in places, but the water is calm, the sunsets are open, and prices run lower than at Bophut or Chaweng.
The walking street market in the evening is a genuine local affair rather than a tourist show. Maenam suits budget travelers, long-stayers and families who want space and quiet over scenery.
Choeng Mon: the sheltered family bay
Choeng Mon, at the northeast tip, is our pick for small children. The bay is relatively sheltered and often calmer than exposed stretches, though water conditions still change. At low tide the shallows can stretch out like a giant paddling pool. The headland walks are lovely, and the big resorts here are geared toward families.
The trade-off is that it's a bit out of the way. Dining and shopping mean a drive to Bophut or Chaweng. If your holiday is mostly pool, beach and kids, that's not a trade-off at all.
The quiet south-west: Taling Ngam and the Nathon coast
The southwest coast, from Nathon down through Lipa Noi to Taling Ngam, is a different island. No resort strip, no nightlife, just fishing villages, coconut groves, empty stretches of sand and the best sunsets in the Gulf, since this is the only coast that faces the water as the sun drops behind Koh Tan and the marine park islands.
Swimming varies, with rocky patches and shallows that depend heavily on tide, so it's not the coast for a classic beach holiday. It's for people who've done Samui before, travelers who want silence, and anyone building a trip around sunsets and a good book. There are a handful of resorts along Taling Ngam built precisely for that mood, and they book out with repeat visitors.
Where we'd stay
First time on the island, north Chaweng or Lamai. With small kids, Choeng Mon or Maenam. For charm and evenings on foot, Bophut. For a second trip or a honeymoon, the south-west. And if you want two islands in one holiday, the ferry from the west coast piers to Koh Phangan takes well under an hour, and our Koh Phangan beaches guide covers the quieter side of the Gulf.