The Gulf of Thailand has some of the best party islands and chill beaches in the region — and enough variety between them that different travellers can find their thing without too much compromise. Here's how to choose where to go and what to expect from each island.
Best time to visit
The Gulf coast has the opposite weather pattern to the Andaman side. October to April is the dry season here — calm seas, warm weather, the best conditions for diving and snorkelling. The Gulf's peak season for parties and beach life is November to January.
Getting around
Inter-island ferries link Koh Tao, Koh Pha Ngan, and Koh Samui — book in advance during high season, particularly around the Full Moon Party dates on Koh Pha Ngan when every boat fills up. The ferry from Chumphon or Surat Thani on the mainland is the standard arrival route.
Scooter rental is the way to get around once you're on an island. Check the bike thoroughly before you take it — rental quality varies significantly.
Koh Tao
Koh Tao is the diving island. The waters around it are clear, the dive sites are good, and the Open Water course is cheaper here than almost anywhere in the world. If diving isn't your thing, the snorkelling is still excellent in most bays, and the island is small enough to explore on a scooter in a morning.
New Year on Koh Tao is a serious event — a combination of beach parties, fire shows, and local celebrations that draws a large crowd but maintains more character than the Full Moon experience on Koh Pha Ngan.
Book diving courses in advance during peak season — slots fill up and the better operators book out weeks ahead.
Koh Pha Ngan
Most people know Koh Pha Ngan for the Full Moon Party — a monthly beach rave at Hat Rin that attracts thousands of people. The party is exactly what it sounds like: large, loud, memorable for some, overwhelming for others. If it's not your thing, avoid the island in the few days surrounding the full moon.
Outside of Full Moon, Koh Pha Ngan is genuinely one of the more interesting Gulf islands. The hilly interior has good hiking, the northern beaches (Thong Nai Pan, Bottle Beach) are beautiful and quieter than Hat Rin, and the island has developed a real coworking community with several good beach-facing workspaces. It works well for longer stays — a week or ten days rather than a weekend.
Koh Samui
Koh Samui is the most developed of the three main Gulf islands — it has an international airport, major hotel chains, shopping malls, and all the infrastructure that implies. It's more expensive than Koh Tao or Koh Pha Ngan and has a different crowd.
The recommendation most people give is: get away from the airport and Chaweng Beach (the main tourist strip) and head to the southern and western parts of the island, where the beaches are quieter and the development thins out. Koh Samui has good food, reliable transport, and easy connections to the other islands — it works well as a base even if it's not the most atmospheric of the Gulf options.
Ang Thong National Park
Ang Thong is an archipelago of around 40 uninhabited islands north of Koh Samui, accessible as a day trip or (with advance booking) an overnight camping trip. Kayaking through the islands, snorkelling in the sheltered bays, and the viewpoint hike on the main island are the main draws. Weather-dependent — check conditions before booking because rough seas cancel tours regularly.
The day trip from Koh Samui or Koh Pha Ngan takes a full day. Worth doing if conditions allow.
Practical tips
- Bring cash to smaller establishments and on Koh Tao (fewer ATMs than the other islands)
- Book ferries and diving courses in advance during high season
- Check scooter brakes and tyres before riding — rental bikes are often poorly maintained
- Sunscreen: reef-safe formulas only near marine parks and dive sites
- The Full Moon Party dates are publicly available a year in advance — plan around them accordingly