Koh Samui

Bangkok Airways owns and operates Koh Samui Airport, which gives them a near-monopoly on flights. One-way fares from Bangkok run ฿2,800–6,800. The budget alternative is to fly from Don Mueang to Surat Thani (Nok Air, AirAsia or Lion, often ฿1,000–2,000) and buy the bus-and-ferry ticket at arrivals, 5–7 hours door to door for about ฿1,500–3,000 all in.

Samui is smaller, greener, and more relaxed. Phuket has more dining options, bigger nightlife, and better access to the Similans. Samui wins for couples and wellness seekers, while Phuket suits those who want variety and a busier scene. Samui's Gulf Coast weather also means different monsoon timing, so it's sunny here when Phuket gets rain. The Phuket vs Koh Samui comparison goes through it month by month.

Very much so. Chaweng and Choeng Mon have shallow, calm water during fair-weather months. The island has water parks, the Samui Aquarium, and plenty of villa-style accommodation with pools and kitchens. Roads are fairly safe compared to smaller islands, and international food is easy to find.

Samui sits on the Gulf Coast, so its monsoon hits October through December, the opposite of Phuket and Krabi. November is the wettest month, with occasional flooding on lower roads. January through September is dry and warm, which makes Samui my pick as a rainy-season alternative to the Andaman side.

Samui from April to September, when it stays fairly dry while Phuket and Krabi get the monsoon. From November to March the Andaman pair is the safer call, and from January to March all three are dry, so pick by the trip. Samui for a calm resort island, Phuket for choice and nightlife, Krabi for scenery and lower prices. My Phuket vs Krabi vs Koh Samui comparison goes through all three, category by category.