City guide

Thailand Islands

Thailand's islands split between two seas, and the difference shapes any beach trip. The Andaman coast in the west, reached through Phuket and Krabi, brings the towering limestone karsts of Phi Phi and Railay; the Gulf coast in the east is home to Koh Samui, Koh Pha Ngan and the diving island of Koh Tao. It is usually simpler to pick one coast than to cross between them.

Thailand’s islands are split between two seas, and the difference shapes any beach trip. The Andaman coast in the west, reached through Phuket and Krabi, is the land of towering limestone karsts, Phi Phi and Railay, with its calmest, clearest water running roughly from November to April. The Gulf coast in the east, home to Koh Samui, Koh Pha Ngan and Koh Tao, works on a slightly different season and covers everything from full-moon parties to some of the best-value diving in the region.

The two coasts at a glance

If you are choosing where to spend your beach days, start with the sea rather than the individual island. The Andaman side is the more dramatic scenery: sheer cliffs, hidden lagoons and the postcard karst islands you have probably already seen in photographs. The Gulf side is generally calmer and cheaper to island-hop between, with the three big names sitting close enough to combine on one trip.

Andaman coast (west)

Phuket is the largest island and the main gateway, with an airport and boats to everywhere. Krabi and its Railay peninsula bring the limestone cliffs down to the sand, and both are launch points for Phi Phi and the surrounding islands. Browse the whole region on the Andaman coast guide.

Gulf coast (east)

Koh Samui is the resort anchor of the Gulf, with Koh Pha Ngan and the diving island of Koh Tao a short boat ride away. See how they compare on the Gulf and islands guide.

Getting between them

You can island-hop within a coast easily by ferry and speedboat, but crossing from the Andaman to the Gulf usually means an internal flight or a long overland and boat combination. For most trips it is simpler to pick one coast rather than try to see both.

Island tours and day trips

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Detailed island-by-island guides are on the way. In the meantime, the regional pages above cover where each island sits and what it is best for.

Where to go

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Andaman Coast

Thailand's west coast: Phuket, Krabi and the limestone islands of Phi Phi and Khao Lak.

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Gulf Islands

Koh Samui, Koh Pha Ngan and Koh Tao on the Gulf of Thailand, plus the mainland resort town of Pattaya.

4h 30m

From$56

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