Thailand liveaboard diving at a glance: trips from $892 per person · best months Winter and Spring · all levels · known for coral, mantas, whale sharks. 19 listed departures.
Facts checked against live availability · September 2026
Thailand liveaboard diving means the Andaman Sea: the Similan Islands and the more remote sites at Koh Bon, Koh Tachai, Richelieu Rock and Surin, reached on a multi-day boat out of Khao Lak or Phuket. The Similan Islands themselves are granite-boulder country — sculpted swim-throughs, arches and channels draped in healthy hard coral, with turtles and big schools of fusiliers and snapper.
The further north you go, the bigger the encounters get. Koh Bon and Koh Tachai are the manta sites, and Richelieu Rock — a horseshoe-shaped pinnacle off Surin — is Thailand's best shot at a whale shark, alongside seahorses, frogfish and dense fish life on a single rock.
It genuinely suits all levels: plenty of the Similan reefs are gentle and forgiving. But Richelieu and a few exposed sites can run real current, so this is a place where the right boat and timing matter. We help match the route and conditions to your actual experience, not just your card.
Winter, Spring
coral, mantas, whale sharks
all levels
Best time to dive Thailand
The Andaman liveaboard season runs roughly mid-October to mid-May, because the Similan marine park closes for the monsoon from around mid-May to mid-October and no liveaboards are permitted inside. Within the open season, December through April brings the most settled weather and clearest water — ideal for first-timers in the calmer early months. Manta chances at Koh Bon and Koh Tachai, and whale-shark odds at Richelieu Rock, tend to peak from roughly February to April, when late-season plankton draws the big animals in even as visibility softens slightly. That late window is the classic big-fish trade-off.
What you'll see in Thailand — and when
Want to plan around a specific animal? Try the Marine Life Finder.
What you'll dive in Thailand
- Richelieu Rock — Thailand's top whale-shark and macro pinnacle
- Koh Bon & Koh Tachai manta cleaning stations
- Similan granite swim-throughs, arches and boulder channels
- Elephant Head Rock drift dives through boulder tunnels
- Healthy hard-coral reefs with turtles and schooling fish
- Surin add-on on longer Andaman itineraries
The marquee sites you'll dive
Read before you go
Thailand's Similan Islands: A Complete Dive Guide
Pristine reefs, whale sharks, and mantas — everything you need to know about diving Thailand's premier marine park.
Liveaboard Visa Guide: Which Countries Need What
Visa requirements for every major liveaboard destination: Egypt, Maldives, Indonesia, Thailand, Philippines, Mexico, and the tricky ones.
Thailand Similans Trip Report: 5 Days on The Junk
Five days on a traditional wooden liveaboard through the Similan Islands, Koh Bon, Koh Tachai Pinnacle, and Richelieu Rock. Reef mantas, soft coral, tiger tail seahorses, and one of the best-value liveaboards in Southeast Asia.
What a Thailand Liveaboard Really Costs (Cheapest World-Class Diving There Is)
Real 2026 Thailand liveaboard fares from $1,115, plus park fees, flights, gear and tips — and the price-per-dive math that beats the Red Sea and Indonesia.
Thailand diving — common questions
Do I need to be an experienced diver for a Similan Islands liveaboard?
Not for most of it. Many Similan reefs are gentle and well suited to newer divers, which is why this trip works for all levels. That said, Richelieu Rock and a few exposed sites can run noticeable current, so some sites favour comfort and a few logged dives. Tell us your experience and we'll steer you to the right boat and route.
When is the best time to dive Thailand for whale sharks and mantas?
The season runs roughly mid-October to mid-May, since the marine park closes for the monsoon. For the best big-animal odds — whale sharks at Richelieu Rock, mantas at Koh Bon and Koh Tachai — aim for roughly February to April, when plankton draws them in. Earlier months trade slightly fewer giants for calmer, clearer conditions. We'll match the timing to your priorities.
How long are the liveaboard trips and where do they depart?
Andaman liveaboards typically run a few nights up to about a week, departing from Khao Lak or Phuket. Shorter trips focus on the Similans plus Richelieu Rock; longer ones add Surin and more relaxed pacing. The right length depends on how much you want to reach the northern sites. Reach out and we'll match an itinerary to your time and goals.
How do I book a liveaboard trip to Thailand?
Start by reaching out through our concierge service with a short brief — your dates, experience, and what you want from the trip. We'll shortlist trusted boats, check availability, and come back to you personally.
Bookable Thailand dates
Ready to dive Thailand?
Trips from $892 per person
Share a short brief and we'll shortlist trusted boats, check availability, and come back to you personally.
