Thailand has somewhere between 1,400 and 1,500 islands, depending on how you count. Most travellers see four. Pick three or four from the list below, line them up by ferry timetable rather than by famous name, and you have one of the better three weeks you can spend in Asia.
Ko Yao Noi
Forty minutes by longtail from Phuket and a different country entirely. Muslim fishing villages, water buffalo in the rice paddies, and the limestone karsts of Phang Nga Bay rising out of the sea on every side. Stay at Six Senses or, much cheaper, a wooden bungalow at Ko Yao Bay Pavilions. Rent a scooter. Do almost nothing.
For travellers who want James Bond Island scenery without the speedboats.
Ko Lanta Yai
The longest, calmest island in the south Andaman, and the one that has resisted being ruined. A single road runs the length of the west coast, beach after beach, each with maybe two restaurants and a yoga shala. The old town on the east side is half Chinese-Thai, half sea-gypsy, and serves the best curries on the island in a row of stilt-houses over the water.
For travellers who want a beach week without a resort lobby.
Ko Lipe
The southernmost inhabited island in Thai waters, four kilometres from the Malaysian border, and surrounded by the Adang Archipelago — twenty uninhabited islands inside a national park. Walking Street is busier than it should be, but a 200-baht longtail to Ko Adang or Ko Rawi gets you a beach to yourself for the day. Closed mid-May to mid-October.
For snorkellers and divers who want clear water without a liveaboard.
Ko Phi Phi Don
Yes, the day-tripper crowds are real. Stay overnight anyway. From about 5 p.m., when the speedboats from Phuket leave, Phi Phi becomes itself again — a small village wedged between two bays, longtails settling into the shallows, the cliffs above going pink. Skip the party hostels in Tonsai, walk twenty minutes to Long Beach, and you have one of the most photographed islands in the world to yourself.
For travellers who can stomach the boat crowds for the evenings.
Ko Tao
Six kilometres long, and arguably the best place in Asia to learn to dive. Open-water certifications start around 10,000 baht and most schools are excellent — Crystal, Big Blue, New Heaven (which folds in marine conservation work). Above the surface, the island is a cluster of small bays connected by ridiculous scooter-only tracks. Sunset at Sairee, sunrise at Tanote.
For first-time divers and anyone who has not been underwater in a while.
Northern Ko Phangan
Phangan is two islands. One is the Full Moon at Haad Rin. The other — north of Thong Sala, around Bottle Beach and Haad Yuan — is small wooden bungalows, jungle interiors, and beaches you reach only by longtail or a steep road that punishes scooters. Go for a week, do not leave the north, and you will not even know the parties are happening.
For travellers who want Thailand-in-2005 prices without time travel.
Ko Mak
Almost no one travels to the eastern Gulf, three hours from Bangkok by minibus to Trat then a ferry to Ko Mak. That is exactly why you should. Half the island is owned by five Thai families, who have politely declined to sell to developers. The result is empty beaches, no nightlife, and the kind of pace that takes most travellers two days to settle into. Pair it with Ko Kood for a full week.
For couples and writers and anyone with a book to finish.
Ko Kradan
Largely a marine park, almost entirely uninhabited, and home to a single long beach that has won 'best in the world' votes from people who have seen most of the rest. There are four small resorts and a few bungalow operations, no roads, no cars, and barely any phone signal. The colour of the water in the morning, when you are the first one in, is the kind of thing that makes you suspicious of your own eyes.
For travellers who think a beach should be the only thing on it.
How to actually move between them
The two coasts run on different monsoons. The Andaman (west) is best November to April; the Gulf (east) is more forgiving and stays open most of the year. Trying to do both in one trip almost always means a long internal flight — Krabi to Surat Thani via Bangkok — and one wasted travel day. Pick a coast.
Within a coast, the ferries do most of the work. Book through 12Go.asia rather than hotel desks; the same boat is normally 30% cheaper. Speedboats are faster and wetter, slow ferries are cheaper and let you sit on the roof.
Do not over-pack the route. Three islands in two weeks is plenty. Four is the maximum before the ferry days start to outweigh the beach days.
Ready to plan yours?