Diving in Thailand
The world's cheapest place to learn, and some of its best days underwater — on two coasts with opposite seasons.
Is Thailand Good for Diving?
Thailand is two diving countries in one. The Gulf coast — Koh Tao above all — is the world's certification capital: an Open Water course costs ฿10,000–12,000 (less than half the price of most destinations), conditions are forgiving, and the sites are minutes from shore. The Andaman coast is the destination side: the Similan Islands' granite boulder-scapes, the deep-south pinnacles of Hin Daeng and Hin Muang, and Richelieu Rock — routinely ranked among the world's top dive sites — reached by liveaboard from the gateway town of Khao Lak. The two coasts run on opposite seasons, so somewhere in Thailand is always diving well. This guide covers where to learn, where to go once you're certified, how liveaboards work, what everything costs, and the marine-life calendar — with the specific schools and operators worth booking.
Plan where you'll stay
Compare hotel rates across Thailand for your dates — lock in free-cancellation rooms now.
- Compare prices across sites
- Filter for free cancellation
- Secure checkout on the partner site
Compare rates on Booking.com
Largest selection
Compare rates on Agoda
Asia-focused selection
Compare rates on Hotels.com
Member prices
Sponsored — we may earn a commission at no extra cost to you. Learn more.
Key Facts (2026)
Certification: ฿10,000–12,000 on Koh Tao
The 3.5–4 day Open Water course on Koh Tao is the world's best value, often with basic accommodation included. Elsewhere in Thailand expect ฿13,000–18,000. Fun dives run ฿1,000–1,800 each; day trips ฿3,000–6,000 with gear.
The marquee sites
Richelieu Rock (Andaman, via Khao Lak) is Thailand's crown jewel. Then: the Similan boulders, Hin Daeng/Hin Muang off Koh Lanta, Sail Rock between Koh Tao and Phangan, and Chumphon Pinnacle off Koh Tao. The HTMS Chang off Koh Chang is the country's biggest wreck.
Liveaboards: the right way to do the Similans
Boats run 2–5 nights from Khao Lak, roughly ฿20,000–60,000 depending on boat class and length, waking up at the sites before day boats arrive. December–March departures book out well ahead.
Whale sharks are a real possibility
No dive shop can promise one, but Sail Rock, Chumphon Pinnacle and late-season Richelieu Rock are Thailand's best odds, with sightings reported year-round and a loose peak around February–May in the Andaman.
The admin that matters
Travel insurance must say it covers scuba (to your certification depth) — many base policies exclude it. Leave 18–24 hours between your last dive and flying. Log nothing deeper than your training, and pick shops on safety culture, not the last ฿500.
Where to Dive, Coast by Coast
Every Thai dive region has a personality. Match the trip to it and the country over-delivers.
Koh Tao — where the world learns to dive
One small Gulf island certifies more new divers than almost anywhere on earth, and the machine works: calm bays, shallow training sites, dive schools competing hard on quality, and prices — ฿10,000–12,000 for Open Water, often with a bed thrown in — that make the course cheaper than a week of European club diving. Choose your school by personality: Big Blue and Ban's for the full social-resort experience, Crystal Dive for the polished Mae Haad all-rounder, Master Divers for small groups and senior instructors, Roctopus for the high-energy professional outfit, and New Heaven in Chalok for the island's famous marine-conservation program. Certified divers get Chumphon Pinnacle and Sail Rock — the Gulf's two big pinnacles, both with whale-shark form.
Khao Lak and the Similans — Thailand's best diving, full stop
The quiet beach town of Khao Lak is the gateway to the Similan and Surin islands — granite boulder gardens, white-sand channels, and Richelieu Rock, the horseshoe pinnacle that makes world-top-ten lists for its sheer density of life. The park opens roughly mid-October to mid-May, and the liveaboard is the format that does it justice: two to five nights, first boat at every site, ฿20,000–60,000 all-in. Khao Lak Explorer is the town's top-rated modern operation for liveaboards and long-range Richelieu day trips, Sea Dragon has run these waters since the 1990s, and Wicked Diving is the small-group responsible-travel choice. Pair it with a Rawai Muay Thai training block or a beach week — Khao Lak rewards slow trips.
Phuket and Phi Phi — day-trip diving with everything else attached
Phuket is the day-trip hub: morning boats to Racha Yai and Racha Noi, Shark Point's leopard sharks, and the King Cruiser wreck, with operators like Aussie Divers running slick three-dive days. It suits divers whose travel companions don't dive — you're back for dinner. Phi Phi concentrates its own excellent circuit — the Bida islets' walls, turtles and blacktips — with a dense cluster of well-rated shops (DPM, The Adventure Club, Princess Divers) and the option to dive the same sites with fewer boat hours from the island itself.
Koh Lanta and the deep south — the big-animal pinnacles
Lanta's dive shops — Phoenix, Blue Planet, Lanta Diver among a strong field — exist substantially because of two sites: Hin Daeng and Hin Muang, the deep-south pinnacles whose purple soft-coral walls and open-water exposure make them Thailand's best manta odds outside the Similans. Longer runs reach Koh Haa's lagoons and caverns, one of the country's prettiest site groups. Further south still, Koh Lipe dives the Adang archipelago's healthy reefs with small operators like Pura Vida and Adang Sea Divers — Thailand's least-crowded quality diving.
The Gulf islands and the east — Samui, Phangan, Koh Chang
Samui and Phangan share Sail Rock — the Gulf's best site, a chimney-swim-through pinnacle an hour out, run daily by Sail Rock Divers from Phangan and Samui's shops like Silent Divers. Diving here bolts neatly onto island holidays that were never dive trips. And on the east coast, Koh Chang offers the country's biggest wreck — the 100-metre HTMS Chang, a decommissioned warship sunk as an artificial reef — plus easy island reefs, from a low-key dive scene that suits the quiet eastern-gulf route.
Learning to Dive: How the Course Actually Works
The Open Water certification — PADI or SSI, functionally interchangeable in Thailand — takes three and a half to four days: theory (much of it doable online before you fly), confined-water skills in a pool or calm bay, then four open-water dives to 18 metres. Koh Tao's price includes what matters: small groups, all gear, and often basic accommodation; the add-ons worth paying for are a private instructor if you're nervous and the Advanced course (two more days, five dives, 30-metre limit) if you're continuing to the Andaman's deeper sites. Book schools with named instructors and capped groups over the absolute cheapest — the difference is ฿1,000 and the entire quality of your foundation. One health note: diving is off the table with a cold you can't equalise through, and your instructor would rather reschedule than push you.
Already certified but rusty? Every region runs refresher dives (฿1,500–2,500) — take one after a multi-year gap rather than bluffing; the crew will know by the second minute anyway.
What Diving in Thailand Costs
The value curve, roughly: fun dives ฿1,000–1,800 per dive on the Gulf islands with gear; Andaman day trips ฿3,000–6,000 for two or three dives with lunch and gear; long-range Richelieu Rock day trips ฿5,500–7,500; Similan liveaboards ฿20,000–60,000 for two to five nights depending on boat class — budget steel workhorses at the bottom, boutique dive yachts at the top — nearly always including meals, gear and most park fees. Courses: Open Water ฿10,000–12,000 on Koh Tao, ฿13,000–18,000 elsewhere; Advanced ฿9,500–14,000; the conservation add-ons at places like New Heaven price per program. Marine park fees (a few hundred baht per day) are sometimes billed separately — ask, so the boat-day maths doesn't surprise you.
Koh Tao: The Certification Capital
Browse allBig Blue Diving School Koh Tao
PADI-certified diving school on Sairee Beach offering courses and guided dives for all experience levels.
Roctopus™ | Koh Tao Diving Center
A highly rated dive centre on Sairee Beach offering courses and dive trips for all experience levels.
Master Divers
Koh Tao's quality-first dive school — small groups, senior instructors and a serious conservation ethic, the island's answer to divers who want depth over party.
Crystal Dive Koh Tao
Koh Tao's big five-star PADI career centre in Mae Haad — pools on site, eco programs, and the island's classic all-levels dive operation.
Ban's Diving Resort
The certification giant of Koh Tao — a full resort campus in Sairee that has trained more divers than almost anywhere on earth, with pools, rooms and a famous social scene.
New Heaven Dive School
Chalok's conservation-famous dive school — home of Koh Tao's marine conservation program, where reef restoration is taught alongside the PADI ladder.
Where to stay in Koh Tao
Compare live hotel rates for the Koh Tao stops in this guide.
- Compare prices across sites
- Filter for free cancellation
- Secure checkout on the partner site
Compare rates on Booking.com
Largest selection
Compare rates on Agoda
Asia-focused selection
Compare rates on Hotels.com
Member prices
Sponsored — we may earn a commission at no extra cost to you. Learn more.
Khao Lak & the Similan Liveaboards
Browse all
Khao Lak Scuba Adventures
A highly regarded dive operator in Khao Lak offering scuba courses, day trips, and liveaboard expeditions.
Sea Dragon Dive Center
One of Khao Lak's original dive operations — Similan liveaboards and day trips run with decades of local experience, from the town that gates the islands.
Wicked Diving
The responsible-travel dive operator in Khao Lak — small-group Similan liveaboards with a conservation ethos and a loyal international following.
Khao Sok National Park
Khao Sok National Park protects one of the world's oldest rainforests — older than the Amazon — draped over dramatic limestone karsts in southern Thailand between Phuket and Surat Thani.
Where to stay in Khao Lak
Compare live hotel rates for the Khao Lak stops in this guide.
- Compare prices across sites
- Filter for free cancellation
- Secure checkout on the partner site
Compare rates on Booking.com
Largest selection
Compare rates on Agoda
Asia-focused selection
Compare rates on Hotels.com
Member prices
Sponsored — we may earn a commission at no extra cost to you. Learn more.
Phuket & Phi Phi Day Boats
Aussie Divers Phuket
Rawai-based dive operation offering PADI courses and fun dives, run by owner Darren Gaspari.
Scubadeep Phuket
A scuba diving centre in Kathu offering guided dives and certification courses for all experience levels.
Merlin Divers
A well-regarded Kamala-based dive centre offering guided dives and certification courses across Phuket's top sites.
DPM Diving Koh Phi Phi
SSI-affiliated scuba diving centre on Koh Phi Phi offering courses and guided dives for all levels.
The Adventure Club - Scuba Diving Phi Phi Island
A well-regarded Phi Phi Island dive operation offering beginner dives through to full certification courses on the Andaman Sea.
Princess Divers - Scuba Diving Phi Phi Island
Highly regarded dive operation on Phi Phi Island offering Open Water certification courses and guided fun dives.
Where to stay in Phuket
Compare live hotel rates for the Phuket stops in this guide.
- Compare prices across sites
- Filter for free cancellation
- Secure checkout on the partner site
Compare rates on Booking.com
Largest selection
Compare rates on Agoda
Asia-focused selection
Compare rates on Hotels.com
Member prices
Sponsored — we may earn a commission at no extra cost to you. Learn more.
The Deep South: Lanta & Lipe
Phoenix Divers - Koh Lanta Diving, Freediving, Snorkeling
PADI-certified dive centre in Sala Dan offering scuba courses, freediving, and snorkeling trips across the Andaman Sea.
Blue Planet Divers Koh Lanta
A highly regarded scuba and freediving centre on Koh Lanta, open daily with courses for all levels.
Lanta Diver – Koh Lanta Diving and Snorkeling
A highly regarded dive shop in Sala Dan offering scuba diving courses, dive trips, and snorkeling tours around Koh Lanta.
Pura Vida Diving Koh Lipe Dive Center
A well-regarded dive centre on Koh Lipe offering guided dives and courses in the Andaman Sea.
Best Trip Lipe Travel
A highly rated tour operator on Koh Lipe offering island-hopping and sea activities in the Andaman.
Where to stay in Koh Lanta
Compare live hotel rates for the Koh Lanta stops in this guide.
- Compare prices across sites
- Filter for free cancellation
- Secure checkout on the partner site
Compare rates on Booking.com
Largest selection
Compare rates on Agoda
Asia-focused selection
Compare rates on Hotels.com
Member prices
Sponsored — we may earn a commission at no extra cost to you. Learn more.
Gulf Pinnacles: Samui & Phangan
Silent Divers
A highly regarded PADI dive centre on Chaweng Beach Road, offering courses and guided dives for all levels.
The Dive Academy Koh Samui
A PADI-certified diving school in Bo Put offering guided dive tours and courses for all levels across Koh Samui's reefs.
Sail Rock Divers
A highly regarded dive centre on Koh Pha-ngan offering PADI courses and guided dives to Sail Rock and beyond.
Where to stay in Koh Samui
Compare live hotel rates for the Koh Samui stops in this guide.
- Compare prices across sites
- Filter for free cancellation
- Secure checkout on the partner site
Compare rates on Booking.com
Largest selection
Compare rates on Agoda
Asia-focused selection
Compare rates on Hotels.com
Member prices
Sponsored — we may earn a commission at no extra cost to you. Learn more.
Plan the dive trip:
Frequently Asked Questions
Common questions about diving in thailand.
Where to stay during your trip
Start with Koh Tao below — this guide also covers Khao Lak, Phuket, Phi Phi Islands, Koh Lanta, Koh Lipe, Koh Samui, Koh Phangan, all searchable on each booking site.
- Compare prices across sites
- Filter for free cancellation
- Secure checkout on the partner site
Compare rates on Booking.com
Largest selection
Compare rates on Agoda
Asia-focused selection
Compare rates on Hotels.com
Member prices
We may earn a commission from bookings made through these links — at no extra cost to you. Learn more.
Explore More in This Guide
You Might Also Like
5 Days in Phuket
Two boat days, one culture day, two beach days — based in Kata so nothing is more than an hour away.
7 Days in Thailand
Capital, mountains, islands — six nights, two short flights, and no day lost to transit.
Things to Do in Koh Samui
The Gulf's glamour island — boat days, temple mornings, and fire-show nights
Thailand Honeymoon Guide
Private pool villas, longtail sunsets, and evenings made for two.
Best Time to Visit Thailand
Plan around the weather, not against it
Ready to build your itinerary?
Use our free itinerary builder to save places, organise days, and share your trip.
Open Itinerary Builder