Snorkeling and Diving Around Koh Chang: What to Expect Underwater

The waters around Koh Chang and its neighboring islands are home to colorful coral reefs, reef sharks, and even the occasional whale shark during peak season. Whether you are a first-time snorkeler or a certified diver, here is what you need to know.

Best Snorkeling Spots

Koh Rang National Marine Park — A cluster of uninhabited islands about 45 minutes by speedboat from Bang Bao. The coral here is among the healthiest in the Gulf of Thailand, with visibility reaching 15–20 meters on good days. Expect to see angelfish, butterflyfish, moray eels, and blue-spotted stingrays.

Koh Wai — A smaller island with a house reef just steps from the beach. Ideal for beginners — the water is shallow and calm, and the coral starts at waist depth.

Koh Man Nai — Known for its sea turtle population. Hawksbill and green turtles are regularly spotted here between November and March.

Diving Highlights

HTMS Chang Wreck — A decommissioned Thai Navy vessel sunk in 2012 as an artificial reef. Sitting at 30 meters, it is now encrusted with soft corals and home to barracuda, grouper, and the occasional bamboo shark. Suitable for Advanced Open Water divers.

Hin Luk Bat — A submerged pinnacle south of Koh Rang with strong currents that attract pelagic fish. On lucky days, you may encounter whale sharks between February and April.

When to Go

Practical Info

• Several dive shops operate from Bang Bao and Lonely Beach. A two-dive trip typically costs 3,000–4,000 THB including equipment.
• Snorkeling day trips to Koh Rang depart daily in high season (Nov–Apr) at around 1,500 THB per person.
• The hotel concierge at Sylvan Koh Chang can arrange private boat charters for groups.
• Reef-safe sunscreen is strongly encouraged — the marine park is a protected area.