Best for: Resorts, couples, ease of access
Thailand's second-largest island with a well-developed resort scene, international airport, and reliable infrastructure. Tilted upmarket in recent years.
Thailand Islands Guide
Thailand has over 1,400 named islands scattered across two seas. They range from international resort destinations with their own airports to remote uninhabited atolls reachable only by chartered longtail. The critical planning choice is which coast to visit — the Gulf of Thailand (east) and the Andaman Sea (west) have different weather seasons, different character, and different best routes. This guide covers the standout islands on both coasts with honest notes on who each one suits.
Gulf of Thailand: Best season December–August. Ferries from Surat Thani, Chumphon, and Bangkok (overnight trains). Islands: Samui, Phangan, Tao, Chang.
Andaman Sea: Best season November–April. Access via Phuket, Krabi, or Satun. Islands: Phi Phi, Lanta, Lipe, Trang group.
Gulf of Thailand Islands
Best for: Full Moon Party, yoga, diving
Famous for the monthly Full Moon Party at Haad Rin beach, but increasingly popular year-round for yoga retreats, wellness, and quieter west-coast beaches.
Best for: Diving, budget travel, snorkelling
One of the world's best and most affordable dive destinations. Small, walkable, with a friendly traveller community and excellent shallow snorkelling.
Best for: Jungles, waterfalls, quiet beaches
Thailand's second-largest island, near the Cambodian border. Lush jungle interior, quiet beaches, and far fewer tourists than the Gulf big three.
Andaman Sea Islands
Best for: Families, luxury, convenience
Thailand's largest island and most visited destination. Full range of accommodation, beaches for all tastes, and a gateway to the Andaman. Its own airport.
Best for: Scenery, snorkelling, party
Dramatic limestone scenery and clear turquoise water. Now managed with visitor limits following years of overcrowding. Stay overnight for a calmer experience.
Best for: Relaxed families, long stays
A long, hilly island with a genuinely relaxed pace and several good beaches. Less developed than Krabi or Phuket, and popular with families and longer-stay visitors.
Best for: Off-the-beaten-path, snorkelling
Near the Malaysian border in Satun province. Remote enough to filter casual visitors, with extraordinary water clarity and a tiny pedestrianised village.
Best for: Hidden gems, budget
Koh Mook, Koh Kradan, and Koh Ngai are among Thailand's most underrated islands — beautiful, affordable, and genuinely off the main tourist trail.