Artificial reef
down to 12 m
Junkyard Reef
- Open Water
- Batfish
Koh Tao
Diving in Thailand
16 documented dive sites, 10 of them for Open Water divers. Known for whale sharks, turtles and stingrays.
- Best months
- Mar–May, Sep–Oct
- Water
- 26–30 °C
- Levels
- Open Water, Advanced
When to go
Pick a month: the diving season, from published sources, and the typical weather.
Pick a month
- Best
- Good
- Possible
- Closed
- Not documented yet
Koh Tao in October
Best season- Sea
- 30 °C
- at the surface
- Air
- 29 °C
- 26 °C at night
- Rain
- 280 mm
- one of the wettest months
- Wind
- 15 km/h
- on average
Typical weather, not a forecast: averages for 2021–2025 (air, rain, wind) and 2023–2025 (sea), data from Open-Meteo (ERA5 / Copernicus, Météo-France). Covers an area of roughly 10 to 25 km around the destination.
Big Blue Diving (Koh Tao operator): March–May best (calm sea, best visibility, whale shark season); late Jan–early Mar calm but visibility temperamental after the monsoon; Jun–early Aug breezy with waves on the west coast (dive the east side); Sep–Oct calm seas with good whale shark chances; Nov–Dec monsoon with reduced visibility, diving still possible (SSI). Best windows: Jan–Apr and late Aug–early Nov.
Dive sites in Koh Tao
From the easiest to the most demanding. Levels with a dashed outline are estimates we are still verifying.
Open Water friendly
usual dive down to 18 m10 sitesReef
down to 14 m
Lighthouse Bay
- Open Water
- Blacktip reef sharks
Reef
down to 22 m
White Rock
Rocky reef averaging 12 m with mild to no current most of the year, where sea turtles are often seen feeding on soft corals.
- Open Water
- Turtles
Reef
down to 16 m
Aow Leuk
Shallow east-coast bay averaging 8 m with a sandy training area, where blacktip reef sharks patrol the shallows and seahorses hide in the sand.
- Open Water
- Blacktip reef sharks
Reef
down to 20 m
Hin Wong Bay
- Open Water
- Blacktip reef sharks
Reef
down to 18 m
Japanese Gardens
Shallow Koh Nang Yuan bay from 2 to 18 m that often has good visibility, a classic site for beginners.
- Open Water
- Eagle rays
down to 20 m
Twins
Two rocks off Koh Nang Yuan from 6 to 18 m, home to saddleback clownfish in their anemones.
- Open Water
- Clownfish
Reef
down to 14 m
Pottery Pinnacle
- Open Water
- Stingrays
Artificial reef
down to 18 m
Tanote Bay
- Open Water
- Blacktip reef sharks
For Advanced divers
usual dive down to 30 m6 sites
Chumphon Pinnacle
Granite pinnacle 12 km northwest of Koh Tao, the site where Black Turtle Dive logs its most whale shark sightings, amid huge schools of trevally and snapper.
- Advanced
- Pinnacle
- Whale sharks
Rock formations
down to 32 m
Green Rock
Boulder site with small caves and swim-throughs, triggerfish nests and yellowtail barracuda schools.
- Advanced
- Barracuda
Pinnacle
down to 40 m
Sail Rock
Offshore rock between Koh Tao and Koh Phangan with a vertical Chimney swim-through from 5 to 18 m and thousands of barracuda.
- Advanced
- Whale sharks
Marine life
When the big encounters happen, month by month.
| Species | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Whale sharksSource: bigbluediving.com |
- Peak season
- Seen
Whale sharks: Mar–May, Sep–Oct
Also reported here, season not documented yet:
- Turtles
- Stingrays
- Barracuda
- Trevally
- Clownfish
- Groupers
- Manta rays
- Leopard (zebra) sharks
- Brydes whale
- Sea snakes
Where is Koh Tao?
Somewhere quieter?
Koh Tao is one of the busiest dive hubs in the world. These destinations dive in a similar way and see far fewer divers: Southern Leyte (Sogod Bay), Siquijor and Sipadan & Semporna.
See all alternatives to Koh Tao →Koh Tao: frequently asked questions
- When is the best time to dive Koh Tao?
- The best months to dive Koh Tao are Mar–May, Sep–Oct. Big Blue Diving (Koh Tao operator): March–May best (calm sea, best visibility, whale shark season); late Jan–early Mar calm but visibility temperamental after the monsoon; Jun–early Aug breezy with waves on the west coast (dive the east side); Sep–Oct calm seas with good whale shark chances; Nov–Dec monsoon with reduced visibility, diving still possible (SSI). Best windows: Jan–Apr and late Aug–early Nov.
- Is Koh Tao good for beginner divers?
- Yes, partly: 10 of the 16 dive sites we document are suited to Open Water divers, including Junkyard Reef, Lighthouse Bay and Mango Bay. The others need more experience or a higher certification.
- What is the water temperature in Koh Tao?
- The water is usually between 26 °C and 30 °C over the year.
- What marine life can you see in Koh Tao?
- Divers regularly see whale sharks (Mar–May, Sep–Oct), turtles, stingrays, barracuda, trevally and clownfish.
About this page
Seasons and marine life come from the sources below. Site levels and depths marked as estimated come from our original catalogue and are being checked one by one. Conditions change: always confirm with a local dive centre.
Your next dive is somewhere out there.
Find my next dive tripPhoto credits
- Mango Bay, Koh Tao, ScorpioZZ, CC BY 3.0, via Wikimedia Commons
- Pink anemonefish at Chumphon Pinnacle, Koh Tao, yeowatzup, CC BY 2.0, via Wikimedia Commons
- Sunlight and bubbles in deep blue water, Sarah Lee, Unsplash License, on Unsplash
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