Koh Tao

Why diving is the whole point

Koh Tao sits on the western side of the Gulf, sheltered from the worst of the monsoon, and its dive sites are mostly within a short boat ride of the main beach. That combination — calm water, short crossings and shallow reefs — is exactly what makes it work as a place to learn.

It issues a very large share of the world's entry-level diving certifications, which cuts both ways: prices are low and competition is fierce, and the quality of instruction varies more than it should. Choose the school, not the price.

If you already dive, the sites around Koh Tao and neighbouring Koh Nang Yuan are pleasant rather than spectacular — the region's best diving, around the Similan Islands, is on the other coast entirely.

Choosing a dive school

This is the single most important decision on the island, and the one people most often get wrong by shopping on price alone.

• Group size. Ask directly how many students per instructor. Four is reasonable; eight is not, whatever it costs.
• Whether you get the same instructor for the whole course, and whether the pool sessions are actually in a pool.
• Whether the school is a member of a recognised training agency and whether the instructors are certified to teach, not just to dive.
• Read recent reviews for safety mentions specifically, not for how fun the staff were.
• Never accept a course that skips confined-water training or offers to certify you without the required open-water dives.

If you do not dive

Koh Tao is still worth a visit without a certification. The snorkelling off Sairee, Chalok Baan Kao and especially around Koh Nang Yuan is good, and the island is small enough to explore by scooter or on foot.

Viewpoints such as John-Suwan and the two bays at Nang Yuan are the standard photographs, and they are genuinely worth the climb. The island is also a common stop on the Gulf route between Samui and the mainland.

When to go

The Gulf pattern applies: the island is at its best roughly from February to September, and wettest from October to December, when crossings get rough and some dive sites are closed.

Visibility is generally best in the first half of the year. Water temperature stays warm enough for a short wetsuit or even a rash guard year-round.

Getting there

There is no airport. Everyone arrives by ferry, and the crossings are the part of the trip most likely to be unpleasant in bad weather.

• From Koh Samui — the shortest crossing, around two hours, several times a day.
• From Koh Phangan — around an hour and a half.
• From Chumphon on the mainland — around two to four hours depending on the service, and the usual route if you are coming overland from Bangkok.
• From Surat Thani — a longer combination of bus and boat.
• High-speed catamarans and slower overnight boats both run; the fast ones are more comfortable and much less so in a swell.