Diving in Thailand: Where, When and What It Costs

Where are the best dive areas in Thailand?

Five areas cover almost all the diving in Thailand, split between two coasts.

When is the best time to dive in Thailand?

Pick the coast to match your month: the two seas swap seasons.

The water stays between 27 and 30 °C all year on both coasts: a 3 mm shorty or even a rash guard is enough. For the rest of your trip, the weather month by month is in our when to go guide.

Koh Tao: why is it the place to learn?

A 21 km² island in the Gulf, with more dive schools than hotels on some beaches.

Koh Tao works because everything is close: the dive sites are 5 to 30 minutes by boat, the bays on the east and south coasts are sheltered, and the depth around the island rarely goes past 30 metres. Competition between schools keeps prices low and the teaching well oiled: you can arrive in the morning, start your course the same afternoon and be certified three days later.

Most schools sit on Sairee Beach, the lively west-coast strip, and in Mae Haad, where the ferries land. Chalok Baan Kao in the south is quieter and closer to the southern bays. Our Koh Tao guide covers the beaches and where to stay, and Bangkok to Koh Tao explains how to get there by train, bus or plane plus ferry.

Try-dive, Open Water or Advanced: what does it cost?

Three levels, and the prices below include equipment, boat, instructor and certification.

On the Andaman coast, the same courses usually cost 20 to 40 % more, because boats travel further and national park fees apply. The Open Water starts with theory (online or in the classroom) and pool or shallow-water skills, then four dives in the sea; the Advanced adds a deep dive, navigation and three dives of your choice, such as wreck, night or buoyancy.

How do you choose a good dive school?

PADI or SSI matters much less than the instructor and the group size.

PADI and SSI certifications are recognised everywhere in the world, and you can dive with either card at any school. SSI courses on Koh Tao are often a little cheaper; PADI is more widespread elsewhere. What really makes the difference is the number of students per instructor, the condition of the equipment and the time taken over each skill.

• Ask how many students per instructor: four at most is a good sign.
• Look at the equipment and the boat before paying: well kept regulators, a first aid kit and oxygen on board.
• Check that the course includes a dive computer, or at least one per buddy pair.
• Read recent reviews that mention the instructors by name.
• Tell the school honestly about any medical history: they will ask you to fill in a medical questionnaire.

Learning in your own language makes the theory much easier. On Koh Tao, as well as in Khao Lak, Phi Phi and Koh Lanta, several schools have French- or German-speaking instructors, and a few are run entirely in those languages: say so when you get in touch, and book a few days ahead in high season.

Similan, Phi Phi, Lanta, Lipe: diving the Andaman Sea

Bigger fish, clearer water and higher prices than in the Gulf, from November to April.

Is a liveaboard worth it?

For the Similan and Surin Islands, yes: it is the only way to dive the remote sites early and late.

A liveaboard is a boat you sleep on for three to five days, with three or four dives a day. Most leave from Khao Lak or Phuket between late October and early May. Allow roughly 20,000 THB for a basic three-day trip and 40,000 THB or more for four to five days on a comfortable boat, plus park fees.

The Advanced certification is often required, or at least recommended, because several sites are deeper than 18 metres with currents. If you only have the Open Water, some boats let you do the Advanced on board.

Not a diver? The best snorkelling

Many of the best sites can be seen from the surface, with a mask and fins.

• Koh Tao: Shark Bay, Aow Leuk and Hin Wong straight from the beach, and the boat tour around the island with Koh Nang Yuan.
• Similan: speedboat day trips from Khao Lak with three or four snorkelling stops.
• Phi Phi: Bamboo Island and the Phi Phi Leh bays by longtail or speedboat.
• Koh Lipe: reefs a few metres from the beach, and the islands of Koh Adang and Koh Rok.

Wear a rash guard and use reef-safe sun cream: several national parks ban oxybenzone creams. Do not touch or stand on the coral.

Insurance and health: what to sort out before diving

A few simple checks let you dive with a clear mind.

Many travel insurance policies cover recreational diving within your certification level, sometimes as an option. Check the depth limit in the policy, and that it applies to try-dives and courses too. Our travel insurance guide explains what to look for. Some schools include basic dive cover in the course price: ask.

• Leave 18 to 24 hours between your last dive and a flight.
• Do not dive with a cold or blocked ears: wait a day.
• Go easy the evening before a dive: Koh Tao’s bars will still be there afterwards.