Diving Thailand has many options for all levels and types of diving. As a whole diving Thailand can be dived all around the year. The gulf of Thailand is best to dive between the months of May to November and the West coast is best from Nov to April. Thailand is very accessible and easy to get around by minibus, bus train or plane. Food and accommodation are relatively cheap and you’ll probably find the highest concentration of dive shops in Asia here. I have dived many places around Thailand, taken lots of courses there and also certified numerous students here. I have been based in Koh Lanta now for many years teaching, managing a dive shop called Ocean Divers and now I work for Lanta Diver as a professional Underwater photographer.
One of the nice things about Diving Thailand are the warm waters, temperatures barely get below 27°C. This allows you to dive in boardies and a rash guard rather than wetsuits . Wetsuits (mainly shorties) are provided by most dive shops but not really needed unless you feel the cold. Take care in the sun and drink lots of water so to avoid sun burn and dehydration. Temperatures above the water are usually around 29 – 36°C.
Diving Thailand is basically split between the East coast and the West Coast. On the East coast is the Gulf of Thailand and the world-famous island of Koh Tao. There are other good spots to dive in the Gulf such as Koh Chang, Koh Phangan and Samui. Most dive sites are within an hour of the beach and you can choose between speedboat or big boat diving. Be sure to check any rental equipment that you hire out as the quality can vary from shop to shop. Koh Tao is one of the cheapest places to learn to dive in Thailand. It has the 3rd highest number of yearly PADI certifications in the world. Read more about Koh Tao in my Travel Journal as well as Diving Koh Tao as I spent 4 months there doing my Dive Master Course.
Apart from the cheap prices, one of the main attractions on Koh Tao are the Whale Sharks – Around May – Aug. Koh Tao has some good dive sites if you ask for them. Koh Tao also boasts a great party scene, so mix that with diving and the island can be quite hedonistic.
On the West coast of Thailand are the world-famous Similan Islands in the Andaman sea. Further down from The Similian Islands are Phuket, Phi Phi, Koh Lanta and Koh Lipe. The Similains are famed for Mantas and Whalesharks as well as macro life. the Similains are best explored on a liveaboard as there are many fantastic sites to explore. The best time to go on the Similians is around March time as the prices are a little cheaper and the vis is good. Always check with the operator before you go as weather patterns do change. For the amount of divers Phi Phi has on it year round the corals and marine life here are great. Expect to see sharks, turtles, plenty of nemos and good macro life. Koh Lanta is also very good, I have lived and worked there now for over 6 years.
I found the coral and the marine life to be better on the West coast. I found the west coast a little more diversified and the standard of living a lot more relaxed. Apart from Phi Phi, with its party attitude you can find some relaxing times on the West coast. Generally on the whole the diving much better on the west coast than the east.
Even if you forget some gear on your dive trip, getting any type of dive equipment (regs to BCD’s to wetsuits to camera equipment) in Thailand is very easy. Places like Phuket and Koh Tao have many dive retailers with big shops and a good range of all the big brands. Even if you are on a smaller island generally most dive shops have catalogues where you can order in any equipment you need within 5 days.