Koh Taen

Koh Taen sits about 20 minutes by longtail boat from Thong Krut Pier or Bang Kao, on Koh Samui’s south coast, and local operators rate its reef as the best snorkeling around the island. There’s no entry fee for the island itself, but you’re paying for the boat — no scheduled public ferry runs here, only tour boats and chartered longtails.

The reef sits close to shore and shallow enough that low tide exposes stretches of it entirely, leaving natural tidal pools with sea anemones, small crabs, and fish stranded until the water returns. Snorkeling here means parrotfish, angelfish, and smaller reef species moving through coral formations just a few meters out — manageable for beginners and reasonably confident kids, since you’re rarely out of your depth. The main beach on the northern shore has soft sand and calm water for swimming without needing a mask at all.

Koh Taen is undeveloped — no resort, no restaurant row, just the island and the reef. That’s the appeal, but it’s not untouched wilderness either: Thong Krut’s tour operators run regular snorkeling trips here, often pairing it with nearby Koh Madsum (“Pig Island”), so expect other boats around, particularly late morning when the day-trip fleet arrives. Go earlier if you want the water closer to yourself.

Almost every seaside restaurant along the Thong Krut waterfront doubles as a boat-trip booking desk, and most quote a flat per-boat rate rather than a per-person one — useful if you’re travelling as a small group, less so solo, since you’re covering the full 1,500 THB either way unless you join a shared tour instead of chartering privately. Some operators extend the run to include Koh Rap or Koh See further out, so it’s worth asking what’s included before you commit rather than assuming Koh Taen is the whole itinerary.

Watch out: the exposed reef flats at low tide look walkable but the coral is sharp and easy to cut yourself on — wear reef shoes or fins rather than bare feet, and never stand directly on live coral.

Book a spot on a shared snorkeling tour or charter a longtail privately from Thong Krut — a private boat runs roughly 1,500 THB, split among however many people you bring, regardless of group size. There are no facilities on the island itself, so bring water, reef-safe sunscreen, and your own snorkel gear if you have it.

For another Samui-area island trip, Mu Ko Ang Thong Marine National Park is a full-day boat excursion further afield with viewpoints and a lagoon.