Responsible snorkelling and diving in Thailand

Thailand’s dazzling islands and beaches draw travellers from across the globe, and many of those visitors want to explore the colourful underwater world with diving and snorkelling trips. However, this puts pressure on Thailand’s reefs and, sadly, has resulted in damage to coral caused by careless boat operators and unwitting tourists. In an attempt to counter this and promote responsible tourism, new regulations were introduced in April 2025. The rules apply to all marine tourism activities in Thailand.

Thailand diving and snorkelling regulations

If you book a diving or snorkelling trip in Thailand, look for a responsible tour operator or dive company.

The new rules require:

• Certified supervision on every trip
• Life vest required for snorkelers (exceptions for anyone certified in free-diving)
• Underwater cameras are only allowed for certified divers with an advanced level or 40+ dives)
• Stay 2 metres above the coral
• Control fins with no kicking up sand near reefs

Not allowed:

• Touching or moving marine life
• Stirring up sediment
• Feeding fish
• Littering in the sea
• Seabed walking

Use reef-safe sunscreen

In addition to the regulations above, travellers should also note that the use of certain sunscreens is not permitted at any of Thailand’s National Parks. This change of law was introduced following studies that revealed the damage to marine life and coral reefs caused by several chemical compounds in sunscreen products. The effects of the harmful chemicals included coral bleaching, destruction of coral larvae, and damage to the coral’s reproductive system. Sunscreens which contain any of the chemicals listed here are banned:

• Oxybenzone (Benzophenone-3, BP-3)
• Octinoxate (Ethylhexyl methoxycinnamate)
• 4-Methylbenzylid Camphor (4MBC)
• Butylparaben

Violators can be fined up to 100,000 baht.

Consider wearing a UV shirt or a rash guard when snorkelling. These offer good sun protection and reduce the need for sunscreen. Rash guards also provide protection against jellyfish stings or minor abrasions. If you do use sunscreen, look for reef-safe sunscreen such as Coral Care.

Advice for divers

Responsible diving in Thailand begins with excellent buoyancy control and a constant awareness of your surroundings. Even experienced divers can accidentally damage fragile coral reefs if they are overweighted or distracted, so taking a refresher dive after a long break is always a good idea. Avoid touching coral, resting on the seabed, or chasing marine life to get closer, particularly in popular dive areas such as Ko Tao and the Similan Islands. Choosing dive operators that limit group sizes and prioritise reef briefings helps reduce overall impact while improving the quality of the dive experience.

• Diving in Thailand: Top tips from the Dive Academy, Ko Samui
• Explore Ko Tao’s underwater world with Nava Scuba Diving

Advice for snorkellers

Snorkellers play just as important a role in protecting Thailand’s marine life, especially in shallow reef areas where coral is most vulnerable. Enter the water carefully from beaches or boats. Keep your body horizontal in the water and be mindful of your fins, as a single kick can break coral that has taken decades to grow. Wearing a rash guard instead of sunscreen helps reduce chemical pollution. Calm, patient observation allows fish and turtles to behave naturally. By keeping a respectful distance and avoiding contact with reefs, snorkellers can enjoy Thailand’s underwater delights without leaving a trace.

Find a responsible operator

Responsible tour operators limit the group size and will include briefings on reef etiquette. They should also use mooring buoys instead of anchors. Avoid any trips that allow wildlife feeding or promote guaranteed sightings of animals or marine life.

Based in Ko Tao, New Heaven Dive School is renowned for its commitment to preserving Thailand’s marine ecosystem and launched the New Heaven Reef Conservation Program (NHRCP) in 2007 to further its conservation efforts. In 2023, NHRCP won the award in the Nature, Marine & Heritage category at the Responsible Thailand Awards.

Best diving and snorkelling sites in Thailand

Thailand is home to several of Asia’s best snorkelling and diving locations. Whether you are a beginner who wants to try some snorkelling or an advanced diver who’d like to enjoy a live-aboard experience, there are lots of options to choose from. See our selection here for more details:
12 of the best locations in Thailand for snorkelling and diving

To protect the marine environment, there are seasonal closures (usually during the rainy season) of reefs and national marine parks. Whatever time of the year you visit, stay safe at the beach and help preserve Thailand’s natural beauty.

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