If you’re planning a diving holiday in Thailand, you’re in for a treat. This tropical paradise is home to some of the world’s most spectacular dive sites, each island offering its own unique underwater experience. From thriving coral gardens and pelagic sightings to beginner-friendly reefs and liveaboard expeditions, diving in Thailand caters to all levels and preferences. Below, we’ll explore the top five Thai islands to dive, starting with our personal favourite: Koh Lanta.
1. Koh Lanta: The Perfect All-Rounder for Divers
Tucked away on Thailand’s Andaman coast, Koh Lanta is an underrated gem with access to some of the country’s most impressive dive sites, including Hin Daeng, Hin Muang, Koh Haa, and Koh Rok. Whether you’re a seasoned diver or just starting out, Koh Lanta offers a wide range of dive experiences—calm lagoon training dives, scenic reef explorations, and thrilling deep dives where manta rays and whale sharks make regular appearances.
It’s also home to Andaman Dive Adventure, one of the island’s most trusted PADI 5-Star dive centres. Their multilingual instructors, high safety standards, and small dive groups make them a top choice for scuba diving in Koh Lanta.
Best for: All levels
Dive highlights: Mantas, whale sharks, pinnacles, caves
Best season: November to April
2. Koh Tao: The Beginner’s Paradise
Known as Thailand’s diver training capital, Koh Tao is famous for its affordable Open Water courses and relaxed backpacker vibe. The island boasts calm, shallow bays perfect for beginners, with vibrant reefs and schools of colourful fish just minutes from shore.
While advanced divers may find the sites less challenging, there are still deeper wreck dives and night dives to enjoy.
Best for: First-time divers, budget travellers
Dive highlights: Japanese Gardens, Chumphon Pinnacle, wreck diving
Best season: March to September
3. Koh Phi Phi: Iconic Beauty and Vibrant Marine Life
While the island is best known for its dramatic cliffs and postcard beaches, Koh Phi Phi also offers fantastic diving. You’ll find limestone walls covered in soft corals, swirling barracudas, turtles, and even the occasional blacktip reef shark.
Dive sites such as Bida Nok and Shark Point are a short boat ride away and well worth exploring. Despite being a party island, Phi Phi’s dive community is surprisingly professional and well-established.
Best for: Intermediate divers, social atmosphere
Dive highlights: Shark Point, Bida Nai, turtles, coral walls
Best season: November to May
4. Similan Islands: World-Class Liveaboard Diving
For those seeking untouched reefs and bigger marine encounters, the Similan Islands are the place to be. Located north of Phuket, this archipelago is only accessible by liveaboard during the dive season—and it’s totally worth it.
The Similans are known for crystal-clear visibility, massive granite boulders, healthy coral reefs, and the chance to spot whale sharks and manta rays. Dive sites like Richelieu Rock and Elephant Head Rock are bucket-list worthy.
Best for: Advanced divers, liveaboard lovers
Dive highlights: Whale sharks, mantas, soft coral gardens, pelagics
Best season: November to May
5. Koh Lipe: Colourful Reefs at the Edge of Thailand
Located near the Malaysian border, Koh Lipe is a small island with access to over 30 dive sites within the Tarutao National Marine Park. It’s less commercial than other islands and offers a peaceful, eco-friendly vibe.
Expect to see healthy reefs, nudibranchs, giant moray eels, and even seahorses. It’s also a fantastic destination for snorkelers and nature lovers.
Best for: Photographers, biodiversity seekers
Dive highlights: Stonehenge, 8 Mile Rock, macro life
Best season: November to April
Plan Your Dive Holiday with Andaman Dive Adventure
From the world-famous Similans to the laid-back reefs of Koh Tao, each of these islands has something special to offer. But if you’re looking for the perfect blend of accessibility, diverse dive sites, and world-class instruction, Koh Lanta stands out as the ideal launchpad for your underwater journey.
Ready to explore the best of scuba diving in Koh Lanta? Visit Andaman Dive Adventure to book your next dive trip, enrol in a course, or plan a custom itinerary tailored to your experience level.