Ko Ngai or Ko Hai is an island that is administratively in Amphoe Ko Lanta of Krabi, but easier to access from Trang (from Pak Meng Pier, 15 km distant on the mainland opposite, in Trang Province). Standard ferries take about one hour. A boat can be rented for 1,500 baht (10 people) or 6,000-10,000 baht (for 20-40 people). A faster speedboat connection from Pak Meng Pier is also available, departing around the same time. It takes just 20 minutes.
From Ko Lanta there is no scheduled ferry service to Ko Ngai although it is possible to rent a private longtail from Saladan (Ko Lanta) during high season (Nov-Apr). Another possibility is to buy an snorkelling trip from Ko Lanta and leave the boat at Ko Ngai.