Koh Mattra

Ko Mattra is one of roughly 40 islands inside Mu Ko Chumphon National Park, and one of only two in the park with anywhere to actually stay — a small homestay called Baan Lung Khao. That overnight option sets it apart from most of Chumphon’s day-trip-only islands, though the majority of visitors still come and go in an afternoon. As a national park island, entry isn’t free: 200 THB for foreign adults (100 THB for children), 40/20 THB for Thai adults and children — a fee that funds park upkeep rather than the resort marketing that free listings sometimes imply.

The shallow reef running along the shore is the reason to come. Giant clams sit among coral heads close enough to see without a boat transfer, and the park has laid out one of its marked underwater nature trails here — a rope-guided snorkel route with placards (some underwater) identifying coral and fish species as you go, useful if you’re snorkelling without a guide. Parrotfish and small reef fish are common in the shallows; visibility depends on the tide and recent weather, best on a calm morning before onshore wind picks up in the afternoon.

Getting here means chartering a longtail or speedboat from the Hat Sai Ri piers near Chumphon town, a crossing of about 45 minutes depending on sea state. There’s no walk-up ferry schedule — book through a Chumphon dive shop, a day-trip operator, or directly with Baan Lung Khao if you’re staying the night. Bring your own snorkel gear if you have a preference on fit; what’s available to rent locally is limited compared to Chumphon’s bigger dive operators on the mainland.

Watch out: Because it’s genuinely low-key — no restaurant row, no beach bar strip — bring cash, water, and any snacks you’ll want; there’s very little to buy on the island itself outside what the homestay provides.

Insider Tip: If you’re combining Ko Mattra with a wider Chumphon island-hopping day, pair it with a stop at Koh Thalu in the same park — the two see far fewer visitors than Chumphon’s better-known dive sites further offshore.

The Chumphon hub covers the mainland piers and other park islands, and Mu Ko Chumphon has the wider national park picture if you’re planning more than one island stop.