Thailand island guide: which of the country's 1,430 islands is right for you?

Thailand has 1,430 islands scattered across the Andaman Sea and the Gulf of Thailand, and picking the wrong one for your trip style — or the wrong season — can make or break a beach holiday. A new roundup from Condé Nast Traveller UK cuts through the choice with a shortlist of 12 islands matched to the kind of traveller you are.

The headline splits are handy. Families get pointed towards Koh Samui, the Gulf coast's big-hitter with resorts and easy infrastructure. Couples after something quieter are steered to Koh Lipe, a tiny island so small you can walk across it, reachable only by ferry or speedboat from the mainland — which keeps the day-trip crowds down. Solo travellers have two picks: Koh Pha Ngan, famous for its full-moon parties but with plenty of quieter corners, and Koh Phi Phi, which also takes the crown for divers and snorkellers thanks to the surrounding reefs and dramatic limestone karsts.

Timing matters more than most people realise, because Thailand's two coasts have opposite monsoon seasons. The west-coast Andaman islands — Phuket, Koh Lanta and Koh Lipe — are at their best from December to April, when the sea is calm and the diving is clear. The east-coast Gulf islands, including Koh Samui and Koh Tao, work better from February to September. So if your holiday falls in July, the Andaman islands will be rainy and rough while the Gulf is in full swing — and vice versa for a February escape.

Phuket is worth a mention in its own right. It's the largest of the islands, has its own international airport, and packs in some of Thailand's top hotels, which makes it the busiest and the most convenient entry point. Krabi and Koh Samui also have air links, so you can skip the overland leg entirely if you'd rather land close to the sand.

Island-hopping is the other thing Thailand does well. You don't have to commit to one island; ferries and boat day trips run regularly between them, letting you sleep at a plush resort and spend a day on a remote islet. From Phuket, for example, a daily ferry crosses to Koh Phi Phi in roughly 45 minutes to an hour.

Why it matters: a Thailand beach holiday is often a once-a-year trip with a long flight attached, so matching island to season and traveller type — family, honeymoon, solo, diving — saves you from the classic mistake of arriving in the wrong monsoon window. The shortlist approach also works if you can only manage one week: pick the island that fits you, then use ferries to add variety without packing up every night.

Story via Condé Nast Traveller UK.