Koh Larn and Koh Si Chang both sit off the upper Gulf coast near Pattaya, and travellers often weigh them up — but they offer almost opposite days out. One is about beaches and water; the other is about quiet, history and atmosphere. Here's how to choose.
Koh Larn — the beach day
Koh Larn is the classic Pattaya beach escape: eight swimming beaches, clear-ish water, snorkeling, every water sport, beachfront seafood, and an easy ~40฿ ferry from Bali Hai. It's busier and more developed, built around sun, sand and sea. If you want to swim, snorkel and lie on a good beach, this is your island.
Koh Si Chang — the quiet escape
Koh Si Chang (reached from Sriracha, further up the coast, not from Pattaya directly) is a different mood entirely: a lived-in Thai island with a former royal palace, Chinese temple, viewpoints and a laid-back town, but far fewer and rockier beaches and little of Koh Larn's water-sports scene. It rewards wandering, history and calm over swimming.
Access
From Pattaya, Koh Larn is the obvious, quick option (short taxi to Bali Hai, short ferry). Koh Si Chang takes more effort — you travel up to Sriracha first, then ferry across — so it's less of a casual half-day and more of a deliberate trip.
Who should pick which
- Want beaches, swimming, snorkeling, water sports, easy access from Pattaya → Koh Larn.
- Want quiet, culture, history, viewpoints and a non-touristy island feel → Koh Si Chang.
- Travelling with kids who want to swim → Koh Larn.
- Want to escape the crowds and don't mind the journey → Koh Si Chang.
The verdict
For a Pattaya beach day, Koh Larn wins on ease and water. For a quiet, characterful island wander, Koh Si Chang is the better fit — just budget more travel time. If it's the beach day you're after, here's how to plan Koh Larn.