🔄 Updated 21 Jun 2026
When people think of snorkeling in Thailand, the Andaman or the lower Gulf usually comes to mind first — but Trat has clear-water spots that hold their own, and with far fewer people around. The heart of it is the Koh Rang archipelago, out in the sea between Koh Chang and Koh Kood, inside Mu Ko Chang National Park. Around it, Koh Kradat and Koh Mak add pretty beaches and clear water too, so it suits both first-timers and anyone who wants to see real coral.
Koh Rang — Trat's best snorkeling
Koh Rang is a cluster of several small islands together — Koh Rang Yai, Koh Rang Lek, Koh Kra, Koh Tian, Koh Yak Lek, Koh Yak Yai, Koh Mapring and Koh Sam Phi Nong. The underwater ecosystem here is the healthiest in the Trat sea, with whole gardens of staghorn coral (Acropora), plus sea anemones and clownfish. Trip boats usually hit several spots in a single day, because each island stands out in its own way.
Sala Chao Beach, on the south side of Koh Rang, is the highlight a lot of people single out. The sand is fine and white, the water a deep blue so clear you can see the sandy bottom, and there's a shallow reef you can drop straight into from the shoreline — good for anyone who doesn't want to swim far out.
Worth knowing
Koh Rang has no resorts or accommodation on the island — it's a day trip, then back to sleep on Koh Chang, Koh Kood or Koh Mak. It's also national-park territory, so there's a separate park entry fee, and Thai nationals pay less than foreigners.
Want more out of Trat? Book tours & activities
Booking online ahead on Klook or GetYourGuide is usually cheaper than the gate and skips the queue. Pick only the experiences you actually want — prices and availability are shown live on each site.
Real snorkel-trip prices, by departure island
The prices below are the ranges we've seen from local operators, and whether the park fee is included or not varies. Check with the shop again before you book, since rates shift with the season and fuel costs.
From Koh Kood — speedboat to Koh Rang
The popular option, since Koh Kood sits close to Koh Rang. A join-in speedboat with resort transfers, lunch and snorkel gear thrown in, usually stopping at Koh Yak Lek, Koh Yak Yai and Sala Chao Beach.
From Koh Mak — full-day wooden boat
A big wooden boat — slower than a speedboat but a comfortable ride, and good for families. It goes to the same Koh Rang spots; some operators charge around THB 830–990 including lunch and gear.
From Koh Chang — Koh Rang snorkel trip
Koh Chang is the furthest of the three from Koh Rang, so the boat ride takes longer. There are half-day trips around the nearer islands and full-day trips out to Koh Rang — pick based on how much time you have.
Group / speedboat packages
Some operators run group Koh Rang snorkel trips from around THB 790, hitting several reef spots in a day. Cheaper, but more people on board — check whether the park fee is included.
Koh Kradat — clear water, a long beach and deer on the island
Koh Kradat is near Koh Mak, and it's the island people talk about for the long white-sand beach you can walk all the way around, and the very clear water. What makes it memorable is the herd of deer living on the island, which you'll see wandering by the shore. Beyond walking around and taking photos, there's reef for snorkeling and room to kayak too.
It's a private island — check first
Koh Kradat is currently a private island. Getting onto it usually means going through a package from the resort on the island, rather than freely boating in on your own like in the past. Before you plan, contact the island/resort to check the latest conditions and entry fees.
Koh Mak — an easy, budget-friendly snorkel base
Koh Mak is part of Koh Kood district — quiet beaches, clear water and a more laid-back feel than Koh Chang. Plenty of people use Koh Mak as a base and take a boat out to snorkel Koh Rang, since it's not far. Koh Mak itself has snorkel spots nearby plus small neighbouring islands to stop at, making it a good fit for anyone who wants a sea trip without the fuss.
Stay on Koh Kood
Closest to Koh Rang, with everything from upscale resorts to mid-range places — a good base if snorkeling is the highlight of your trip.
Stay on Koh Mak
Quiet, laid-back and easy on the wallet, with a convenient boat out to Koh Rang — good for couples and families.
Stay on Koh Chang
Lots of facilities, with plenty of restaurants and activities — but it's the furthest of the three from Koh Rang.
When to go and what to bring
- Clearest water — roughly November to April, when the sea is calm and clear, the best time for snorkeling
- Rainy season (May–Oct) — stronger swell and murkier water, some trips don't run, and the park may close for parts of it, so check ahead
- What to bring — reef-safe sunscreen, a UV rash guard, water shoes, and a waterproof camera if you have one
- Underwater etiquette — don't step on or touch the coral, don't feed the fish, and help keep the reef healthy for the long run
Plan a full Trat sea trip — islands, places to stay and food
See the Trat travel guide →