Koh Tao is the Gulf of Thailand's diving island, and Koh Nang Yuan, a tiny trio of rocky islets just off its north-west tip, is its signature view: three green-topped islands joined by a narrow white sandbar, with turquoise water either side. A speedboat day trip from Samui reaches them in a bit over an hour, and the tour usually combines two or three snorkel stops along Koh Tao's coast with free time on Nang Yuan, where you can swim, walk up to the viewpoint and have lunch. Snorkelling gear and lunch are normally included, and hotel pickups are part of the package. It is a long day on the water but one of the most reliable for clear water and fish life, and it suits anyone comfortable on a fast boat. Visitors who dive can instead book a dive day from Samui, but this snorkelling tour needs no experience at all.
Koh Nang Yuan is privately managed and charges its own small island fee, normally collected on arrival and not always included in the tour price, so check your booking. Visitor numbers are controlled and bags are checked on landing, with single-use plastics restricted, so bring a reusable bottle. The viewpoint climb on Nang Yuan is short and steep, and the sandbar is best before the late-morning crowds, so a tour that gets you to the island early is worth choosing. Snorkel stops on Koh Tao are in sheltered bays where you can expect schools of small reef fish, and sometimes larger visitors if you are lucky.
Sea conditions drive this trip more than any other from Samui. The crossing is exposed, and in the wet season, roughly October to December, swell can make it uncomfortable or lead to cancellations. Speedboats are fast and bumpy, so people prone to seasickness should take tablets, sit near the back and choose a calm-weather day. Big-boat and catamaran versions are slower and steadier, though they use more of the day. Always book with free cancellation if the forecast looks changeable.
A speedboat day suits couples, friends and families with children old enough to swim confidently in a life jacket. Pickups are available from most beach areas, and an early start is the price of seeing the sandbar at its best. If you only have time for one island day trip beyond Ang Thong, this is the one to choose, and the two together make a good pair for a week on Samui.
What to expect
The experience
A speedboat day trip from Samui to Koh Tao and Koh Nang Yuan, with hotel pickup, two or three snorkel stops, lunch and free time on the Nang Yuan sandbar.
Best time
Dry-season mornings are calmest; the wet season brings swell and cancellations, so check the forecast.
How long
About nine hours including pickups, the crossing each way and the stops.
Tips
Bring cash for the Nang Yuan island fee, a reusable bottle, reef-safe sunscreen and seasickness tablets, and be ready for a fast, bumpy ride.
Quick picks
- Best for
- Snorkellers and photographers who want the classic Gulf sandbar view.
- Families
- Fine for confident swimmers with life jackets, but the speedboat can be rough for young children.
- Couples
- Choose a smaller-group departure and walk up to the Nang Yuan viewpoint early.
- Pair with
- Ang Thong for a second island day, or a spa afternoon to recover.
- Time needed
- A full day with an early start.
Good questions
How long is the boat ride?+
A bit over an hour each way by speedboat, depending on conditions and pier. Big boats and catamarans take longer.
Is the Nang Yuan fee included?+
Not always. Many tours collect a small island fee in cash on arrival, so check your inclusions.
Can I do this in the rainy season?+
Trips run when conditions allow, but swell can cause cancellations between roughly October and December. Pick free cancellation.
Do I need to be a strong swimmer?+
You should be comfortable in water with a life jacket and a mask. Guides help beginners, but this is not a trip for non-swimmers who dislike boats.
Can I dive instead?+
Yes, certified divers can book dive days from Samui to Koh Tao, but this tour is for snorkellers.