🔄 Updated 7 Jul 2026
The short version: Southern Thailand has two separate island worlds with opposite rainy seasons, so the first question isn't "which island?" — it's which coast? The Andaman coast (west) is dry and calm roughly November–April. The Gulf coast (east) is at its best January–September and usually stays drier when the Andaman turns wet from May onward. Pick the coast that's dry in your month, base on two or three islands, and connect them by ferry. Trying to do both coasts in one short trip? See how to combine below.
Andaman vs Gulf at a glance
| Coast | Islands | Best months | Fly into |
|---|---|---|---|
| Andaman (west) | Phuket, Krabi/Railay, Phi Phi, Koh Lanta, Koh Lipe | Nov–Apr (driest, calmest sea) | Phuket (HKT) or Krabi (KBV) |
| Gulf (east) | Koh Samui, Koh Phangan, Koh Tao | Jan–Sep (wettest is Oct–Dec) | Samui (USM) or Surat Thani (URT) |
| Shoulder overlap | Either coast works | Jan–Apr both dry; May–Sep favour the Gulf | Match to the coast you choose |
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Plan my trip →Andaman route (~10 days): Phuket, Krabi, Phi Phi, Koh Lanta
The Andaman is the postcard coast: limestone cliffs, longtail boats and clear water. It's your pick for a November–April trip. Fly into Phuket or Krabi and work your way through two or three islands by ferry — no backtracking needed. Deciding on a base? Read Phuket vs Krabi.
- Days 1–3 · Phuket: ease in on the west-coast beaches (Kata, Kamala), old town for food, and a first island day — the day trip or ferry to Phi Phi from here
- Days 4–6 · Krabi (Ao Nang / Railay): take the short ferry across to Krabi, then a longtail to car-free Railay for cliffs, plus the 4-Islands or Hong Islands tour. Tours on the Krabi tickets page
- Days 7–8 · Phi Phi: stay a night or two so you get the bays before and after the day-trip crowds — see our island-hopping guide for the ferry chain
- Days 9–10 · Koh Lanta: slow, flat and quiet — long sandy beaches and sunsets, an easy final stretch before flying out of Krabi. Want it even quieter? See the quietest islands
Where to stay on the Andaman
Phuket for range and flights, Krabi for cliffs and ferries. Our ranked, best-value picks from real guest reviews:
See Andaman hotels →Gulf route (~10 days): Koh Samui, Koh Phangan, Koh Tao
The Gulf islands sit close together in a tidy triangle, so hopping between them is quick. This is your coast for a January–September trip, and the one to choose when the Andaman is wet (May–Oct). Fly into Samui, or fly to Surat Thani and take the boat — see Surat Thani to Koh Samui. Weighing the vibe? Read Koh Samui vs Koh Phangan.
- Days 1–4 · Koh Samui: the biggest, most developed Gulf island — beaches (Chaweng, Lamai), waterfalls, and easy comfort. Tours and transfers on the Koh Samui tickets page
- Days 5–7 · Koh Phangan: a short ferry north — quieter beaches and jungle by day, the Full Moon Party if your dates line up (skip it if that's not your thing; the north and east coasts stay calm)
- Days 8–10 · Koh Tao: the diving island — small, laid-back, and the cheapest place in Thailand to learn to dive or snorkel straight off the beach. See the diving guide before you book
- Getting between them: the Samui–Phangan–Tao ferries run all day and take 30–90 minutes each — buy the next hop when you arrive, no need to lock it in early
Where to stay on the Gulf
Samui for range and flights, Phangan for quieter beaches. Ranked from real guest reviews:
Combining both coasts, and a diving option
You can do both coasts, but only if the calendar allows and you don't mind a travel day in the middle. The clean link is a domestic flight (Krabi or Phuket ↔ Samui), or a longer overland-plus-ferry hop via Surat Thani. In the Jan–Apr window both coasts are dry, so combining works best then. For a diving-first trip, build the route around Koh Tao (Gulf) or the Similan Islands liveaboards off Phuket (Andaman, open roughly Oct–May) — see getting around Thailand for the connections.
- Both coasts, 2 weeks: ~6 days Andaman + a flight + ~6 days Gulf; best Jan–Apr when both are dry
- Snorkel-focused: the clearest water is around Koh Lipe (far south Andaman) and the Similans — see best snorkelling islands
- Diving-focused: Koh Tao to certify cheaply, or Similan liveaboards for reef and bigger fish — see the diving guide
- Families: flat, gentle beaches and short boat rides make Koh Lanta and Samui easiest — see best family beaches
Far-south quiet: Koh Lipe
Right at the bottom of the Andaman, near the Malaysian border — the clearest water and the quietest sand. Best Nov–Apr.
See Koh Lipe hotels →Book the highlights of this trip
The island days and tours travellers add most — compare options and reviews:
Alternative routes: shorter, longer, or a full Thailand trip
This is the beaches-only version. If you'd rather mix in cities and mountains, or you only have a week, here's how to reshape it without rushing.
| You have / want | Suggested route | Skip / swap |
|---|---|---|
| 7 days, beaches only | One base + one hop: Krabi + Phi Phi, or Samui + Tao | Don't try three islands; keep it to two |
| 2 weeks, beaches only | One coast slowly, or both coasts (Jan–Apr) with a flight between | Add a diving day or Koh Lipe |
| City + islands | Add Bangkok before flying south — see the 10-day and 2-week itineraries | Fewer islands, more travel days |
| Travelling May–Oct | Gulf coast: Samui + Phangan + Tao | Skip the Andaman — it's the wet coast then |
🏝️ Phuket vs Krabi
Pick your Andaman base
🌴 Koh Samui vs Koh Phangan
Which Gulf island suits you
⛴️ Thailand island hopping
Ferry chains, Andaman vs Gulf
🗓️ Best rainy-season islands
Where to go when it's wet
💡 Know before you go (for this trip)
Andaman for Nov–Apr, Gulf for Jan–Sep. Getting this right is the single biggest thing separating clear-water photos from three grey, rained-out days.
Island ferries run frequently in high season and are easy to buy locally or through your hotel. The exception is peak holidays, when the popular boats sell out.
Phi Phi and Similan trips wind down in the Andaman's wet months; the Similan National Park is closed roughly mid-May to mid-October. Check before you commit.
If a certification is on your list, budget three or four days on Koh Tao. Similan liveaboards off Phuket are the step up for reef and bigger marine life.
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