Scuba diving and snorkeling in Thailand
Thai diving is known for Koh Tao PADI weeks and Similan liveaboards from Khao Lak. Use it if you want a 3 to 4 day course or a dry-season Andaman boat, not a Bangkok pool lesson.
Koh Tao is known for cheap PADI Open Water weeks, not for a second Full Moon. A 2026 Open Water course runs 9,500 to 12,000 THB for 3 to 4 days. Visibility is easier March to September on the Lower Gulf. Sleep Sairee for the strip or Mae Haad for the pier. Book the boat on [Koh Tao](/koh-tao).
The Andaman side is a different calendar. Similan and Surin national parks open 15 October to 15 May. Day boats and liveaboards leave Khao Lak (Tab Lamu). Foreign marine-park fees run 300 to 500 THB on top of the ticket. Phi Phi and Koh Haa day dives run from Phuket, Krabi, and Koh Lanta from November to April. See [Similan and Surin](/khao-lak/similan-and-surin-islands) and [Phi Phi](/attractions/phi-phi-islands-and-maya-bay).
Where the water is clear, and when boats run
Pick one sea. Tao in the Gulf drier months, or Khao Lak and Phi Phi in the Andaman dry season. Do not stack a Similan liveaboard with a Tao course in the same week. Snorkel days use the same piers and the same park fees.
| Base | Known for | 2026 clock and fee |
|---|---|---|
| Koh Tao | PADI Open Water and cheap fun dives | 9,500 to 12,000 THB; 3 to 4 days; Mar to Sep viz |
| Khao Lak | Similan and Surin day boats and liveaboards | Open 15 Oct to 15 May; 300 to 500 THB park fee |
| Phuket / Krabi / Lanta | Phi Phi and Koh Haa day dives | November to April; park fee extra |
| Snorkel-only days | Same parks, no tank | Same boat desks; confirm the park fee line |
Keep going
Book
- Koh Tao staysCourse week
Sleep Sairee if the shop is on the strip. Mae Haad if the pier is the plan.
Search stays 
Khao Lak staysSimilan boatsSleep Bang Niang if the 15 October to 15 May park window is why you came.
Search stays- Dive and snorkel boatsTours
Name the park and the date. Confirm whether the 300 to 500 THB fee is included.
See tickets
Common questions
- Koh Tao or Similan for a first cert?
- Koh Tao for the PADI week at 9,500 to 12,000 THB. Similan for certified divers on a Khao Lak boat in the 15 October to 15 May window.
- Are marine park fees in the Klook price?
- Often not. Similan and Surin run 300 to 500 THB for a foreign adult. Read the inclusions line.
- When is Phi Phi diving easier?
- November to April from Phuket, Krabi, or Koh Lanta. The Andaman swell is the limiter, not the PADI card.