Most people do Pig Island in the morning, and for the pigs that is the right call. The sunset trip is a different product with a different reason to exist: the light. Here is what the afternoon actually looks like, taken from the sunset speedboat itinerary and from the guests who come back and tell us about it.
The van collects between one and half past two depending on where you stay, working its way south toward the pier. Chaweng and Bophut go first, Lamai last, so a north-coast hotel means a longer ride but an earlier start to the day. The pier is on the quiet south coast, and by the time the boat leaves at three the heat of the day has already started to ease.
The order is reversed from the morning tours. The boat heads straight for Koh Tan and the snorkelling happens while the sun is still high enough to light the reef. Masks, snorkels and vests are on the boat. The reef is shallow, which is good news for nervous swimmers and children, and the fish are close. Our Koh Tan page covers what lives there and why reef-safe sunscreen matters on a reef this close to the surface.
Then the short hop to Koh Madsum. By late afternoon the morning boats have gone, so the beach is quieter than it was at eleven. The pigs have usually eaten well by this point and some will be in the shade, so do not expect the whole herd charging into the water for your fruit. The ones that do come down are lit from the side by a sun that is already turning orange, and that is the photograph this trip is for. Follow the staff on feeding, keep food out of your pockets, and let the pigs decide how close they want to be.
The boat leaves the beach as the sun drops toward Samui. The crossing back is only fifteen to twenty minutes, so the captain takes it slowly and the sunset happens around you rather than behind you. On a clear evening in the calm months this is the best quarter of an hour of the day. On a cloudy one it is still a pleasant boat ride, which is worth saying plainly.
A Thai set dinner is served in the restaurant at the pier, with halal, vegetarian and vegan options if you tell us when you book. The van runs you back to the hotel afterwards, arriving no later than half past seven. It is a gentle end to a gentle afternoon.
Morning if the pigs are the point, or if you are travelling with small children who fade after lunch. Sunset if the light is the point, if you would rather sleep in, or if you have already done a morning trip and want the island in a different mood. In the calm months from February to August both are safe bets; from late October the afternoon sea gets less predictable and we say so on the when to visit page. Either way, bring THB 50 per adult in cash for the landing fee and something you do not mind getting wet.