Short answer: yes — for most first-time visitors to Koh Samui with a full day to spare, Ang Thong Marine Park is worth it. It is a protected archipelago of 42 limestone islands about 30 km west of Koh Samui, and the two things you go for — the Emerald Lagoon (Thale Nai) on Koh Mae Koh and the viewpoint over the islands on Koh Wua Talap — are not something you can see anywhere else in the Gulf of Thailand. Day trips from Koh Samui start from ฿1,200 per adult on a big boat and ฿1,850 per adult on a VIP speedboat, plus a national park fee paid in cash on arrival.
Where it is not worth it: if you are visiting between 1 November and 23 December (the park is typically closed for the monsoon), if you are pregnant or travelling with a baby (the speedboat tours exclude both), if your one free day is really about reef snorkelling, or if you cannot give it a full 8–9 hours. This guide goes through each of those cases using the actual itineraries of the four Ang Thong tours we book, so you can decide with the real numbers in front of you.
What you actually get on an Ang Thong day
Every Ang Thong tour from Koh Samui is a full day — roughly 8–9 hours door to door on the big boat, with hotel pickup between 07:15 and 08:00 and drop-off between 17:00 and 18:00. The crossing is about 1.5 hours each way on the big boat, 45–60 minutes on a speedboat and about 2 hours on the sailing boat. Inside the park the stops are broadly the same on every boat:
- The Emerald Lagoon (Thale Nai) on Koh Mae Koh — a saltwater lake enclosed by rock walls, reached by a marked trail of wooden stairs and walkways. On the sailing tour the walk takes about 15–20 minutes each way.
- Koh Wua Talap — beach time and the viewpoint hike. Every tour page is honest about this one: it is a moderate climb with steep sections and steps, and the speedboat tour puts it at 20–30 minutes uphill. Good footwear matters.
- A snorkelling stop with mask and snorkel provided. Visibility varies with season and tides, and the captain chooses the spot on the day.
- Kayaking — available at the park stops on the VIP speedboat; on the big boat it is an optional add-on, not included in the base price.
- Lunch — a Thai buffet on board on the big boat and sailing tours, lunch at an island restaurant on the private charter.
Ang Thong tour prices from Koh Samui (2026)
| Tour | Price | Day length | Best for |
| Ang Thong big boat tour | From ฿1,200 per adult / ฿800 per child | 8–9 hours, pickup 07:15–08:00 | Budget, families, anyone who wants shade and space on deck |
| Ang Thong VIP speedboat tour | From ฿1,850 per adult / ฿1,500 per child | Full day, pickup 07:30–08:30, return 17:00–17:30 | Less travel time, more time at the stops, kayaking included at the park |
| Ang Thong sailing cruise | See the tour page for the current price | About 9 hours, 08:30 departure | A slow, quiet day; the wider hull rocks less than a speedboat |
| Private Ang Thong speedboat charter | From ฿32,850 per boat (1–10 guests); ฿47,500 for 11–20 | Full day, pickup around 08:00, back 17:00–18:00 | Groups who want their own route and their own pace |
One cost is never in the ticket price: the Ang Thong national park entrance fee, paid in cash on arrival. It is around 250–300 THB per adult depending on the boat (the child rate is lower), and the exact amount is listed in the "Not included" section of each tour page. Bring cash for it. For a fuller breakdown of every option, see our Ang Thong tour price guide.
When Ang Thong is worth it
You are on Koh Samui between late December and October. The park is open, and on a calm day the big-boat trip is one of the best-value full days on the island: breakfast, a Thai buffet lunch, the lagoon, the viewpoint and a snorkel stop for ฿1,200 plus the park fee.
You want scenery more than fish. Ang Thong is a limestone-island landscape first and a snorkelling trip second. If the photos of green water inside a ring of cliffs are what brought you here, this is the only place from Samui that delivers them.
You have a full free day and reasonable fitness. The viewpoint hike is the part people underestimate. If stairs and a 20–30 minute climb in the heat are fine for you, you get the view that makes the trip. If they are not, skip the Koh Wua Talap climb and stay on the beach there; the Emerald Lagoon trail on Koh Mae Koh is the shorter walk (about 15–20 minutes each way on the sailing tour).
You are a group of 8–10. At ฿32,850 for up to ten guests, the private charter works out to roughly ฿3,300 per person — under twice the VIP speedboat price — for your own boat, your own route and as much time in the water as you want.
When it is not worth it
Your dates fall between 1 November and 23 December. Every Ang Thong tour page carries the same line: the park is typically closed in that window for the monsoon season. Do not plan your trip around it in those weeks. A land day at an ethical elephant sanctuary in Koh Samui (from ฿2,850 per adult, no riding) is the usual swap, and our month-by-month guide to Koh Samui covers what else runs in the wet season.
You are pregnant, travelling with a baby, or have a serious back or neck condition. Both speedboat tours state plainly that they are not suitable in those cases because the ride can be bumpy in open water. The big boat and the sailing boat are the calmer options, but this is still a long day at sea.
You really want a snorkelling day. The Koh Tao and Koh Nang Yuan day trip (from ฿1,900 per adult / ฿1,650 per child) is built around the reef, with at least two snorkelling sessions and the three-sandbar beach at Koh Nang Yuan. Ang Thong has one snorkel stop and the visibility is honestly variable.
You cannot give it a full day, or you have young children who will not manage 8–9 hours. The Pig Island and Koh Tan snorkelling trip (from ฿1,350 per adult / ฿1,150 per child) is a 5–6 hour trip with morning and afternoon departures that stays about 4 km off Samui's south coast in calm, shallow water — the usual shorter alternative.
Big boat or speedboat — which one is worth the money?
The honest difference is time and crowd, not the islands. The big boat spends around three hours of the day cruising and has plenty of shaded deck space, breakfast and lunch on board, and a more social atmosphere. The VIP speedboat carries fewer passengers (the tour page gives 16–30 guests), gets to the park faster and uses the saved time for more stops, with kayaks available in the park. It costs ฿650 more per adult. If you are prone to seasickness, the big boat or the sailing boat is the safer choice; if you want to do "everything" in one day and do not mind stairs and a bumpy crossing, the speedboat earns its price.
For a side-by-side of every stop, timing and what is on board, our complete Ang Thong visitor guide goes through each boat in detail.
Is Ang Thong worth it? — frequently asked questions
Is Ang Thong Marine Park worth visiting from Koh Samui?
Yes for most visitors with a full day free between late December and October. The Emerald Lagoon and the Koh Wua Talap viewpoint are unique to the park, and big-boat day trips start from ฿1,200 per adult plus a park fee paid in cash. It is not worth it if the park is closed (typically 1 November to 23 December), if you are pregnant or with a baby, or if you mainly want reef snorkelling.
How much does an Ang Thong tour from Koh Samui cost?
From ฿1,200 per adult (฿800 per child) on the big boat, from ฿1,850 per adult (฿1,500 per child) on the VIP speedboat, and from ฿32,850 per boat for a private speedboat charter for up to 10 guests. The national park entrance fee is extra, paid in cash on arrival, around 250–300 THB per adult depending on the tour.
How long is the Ang Thong day trip?
A full day. The big boat is around 8–9 hours with hotel pickup between 07:15 and 08:00 and return between 17:00 and 18:00; the VIP speedboat picks up 07:30–08:30 and returns 17:00–17:30. The crossing takes about 1.5 hours each way on the big boat and 45–60 minutes on a speedboat.
Is Ang Thong Marine Park closed in November?
Typically yes. The park is usually closed from 1 November to 23 December for the monsoon season, so tours do not run in that window. From late December onwards trips resume.
Is Ang Thong suitable for children?
Children are welcome on the big boat and the VIP speedboat, with life jackets provided and child prices (฿800 and ฿1,500 respectively). Babies are not accepted on the speedboat tours. For younger children or anyone who will struggle with an 8–9 hour day and a viewpoint climb, the 5–6 hour Pig Island and Koh Tan trip is the usual alternative.
