Things to Do in Koh Samui in October

The cooking class led by Geng and the O Family develops in a residential kitchen on Koh Samui's quieter south side. The session begins not at a prep station but at a local market. You'll sort through pyramids of kaffir lime leaves, palm-sugar discs, and still-wriggling prawns. Back at the family compound, Geng walks through the mortar-and-pestle construction of curry paste from raw spice. The sharp burn of galangal mixes with the citrus oil released from bruised lemongrass. The class builds a full multi-course Thai meal from scratch. Each dish is eaten together around a shared table still warm from the wok.

The three-day PADI Open Water Diver Course based out of Koh Samui splits between confined-water sessions in a sheltered pool and open-water dives at sites around the island's southwestern reefs and the nearby Ang Thong marine park. The course moves at a pace that respects beginners without coddling them. By the second day students are descending to twelve meters, equalizing against the pressure while reef fish, unbothered, drift past at arm's length. The warm, soupy water means no wetsuit is necessary. The sensation of breathing underwater for the first time, hearing nothing but the mechanical click-hiss of the regulator and your own amplified exhalation, is disorienting and then profoundly calming.

The sunrise stand-up paddleboard tour launches from Koh Samui's calmer northern beaches before six in the morning. The water is flat as poured glass. The only sound is the soft drip from the paddle blade between strokes. The route hugs the coastline, passing over submerged rock gardens where sea urchins cling to the bottom and small reef fish scatter beneath the board's shadow. As the sun breaks the horizon line, the sea turns from slate grey to copper, then to a pale, almost electric blue. The silhouette of Koh Phangan materializes across the strait. The air at that hour carries the cool mineral smell of the ocean before the day's heat bakes it away.

This full-day tour stitches together three of Koh Samui's strongest draws into a single outing. It begins with the viewpoint at the island's southern highlands, where the panorama drops away to a coastline scalloped with coves and fringed by coconut palms so uniform they look planted by a surveyor. From there the boat crosses to Koh Madsum, known locally as Pig Island, where a small herd of domesticated pigs wanders the beach and wades into the shallows. The snorkeling stop, at a reef shelf between the islets, puts you in water warm enough to stay in for an hour without discomfort. You'll fin over brain coral colonies while parrotfish crunch audibly on the reef below. Lunch arrives on the boat, typically a spread of pad thai, green papaya salad, and grilled chicken fragrant with lemongrass and white pepper.

The Chaweng Beach nightlife walking tour starts after dark on Koh Samui's densest strip. Neon signage bleeds pink and green across wet pavement. The competing bass lines from adjacent bars merge into a single low throb you feel in your sternum. The guide navigates through the main drag and then into the side sois most visitors walk past. You'll stop at a rooftop cocktail spot overlooking the beach, a live-music bar where Thai blues musicians play to a room of thirty, and a street-food cart turning out crispy oyster omelets slicked with sriracha. The tour contextualizes the strip rather than just consuming it. You'll learn which venues are Thai-owned, which sections of Chaweng cater to different crowds, and how the nightlife economy on Koh Samui operates.

The full-day cruise from Koh Samui to Koh Phangan crosses the strait aboard a catamaran that anchors at multiple points along Phangan's western coast. The beaches there are backed by jungle so dense the canopy reads as a solid green wall from the water. The itinerary includes a long swim stop at a sheltered bay where the sand slopes gently into turquoise water. A seafood lunch is served on deck, with the sharp tang of green mango dipping sauce cutting through grilled fish. The slow return is timed so the boat is mid-channel as the sun drops. The sunset from the water, with Koh Samui's ridgeline silhouetted against a sky cycling through amber, rose, and deep violet, is a different experience entirely from watching it onshore. The salt air cools as evening falls. The engine idles down to a murmur for the final approach back to Koh Samui's pier.