Andaman Sea Islands Guide: Best Thai Islands by Trip Style

Andaman Sea islands at a glance

Thailand's Andaman coast runs from Ranong in the north to Satun on the Malaysian border. Phuket is the main gateway, with Krabi, Trang and Pak Bara serving as mainland hubs for the southern islands. Phuket also works as a base for day trips into Phang Nga Bay and toward Phi Phi. Anything farther south or north usually needs at least one overnight. For a wider overview of every coast, read our guide to the Thai Islands Guide: Which Island to Pick by Coast & Season.

• Thai side: Phuket, Phi Phi, Lanta, Trang islands, Lipe, Koh Yao, Similan, Surin.
• Not covered: India's Andaman and Nicobar Islands and Myanmar's Mergui coast.
• Gulf of Thailand islands such as Samui sit on the opposite coast with a different monsoon pattern.

Island groups compared

Each group suits a different pace. Phuket has the most services and the easiest flights. Koh Yao Noi and Koh Yao Yai sit in Phang Nga Bay and feel rural by comparison. Farther south, the Trang islands (Kradan, Mook, Ngai) and Koh Lipe trade convenience for clearer water and fewer crowds. Cost tiers below are qualitative, in our editorial assessment, because no sourced prices were available. Confirm access and timings with operators before you book.

Best time to go to the Andaman Sea islands

Dry-season conditions are the safest bet for boats and clear water. One operator in our research says its island-hopping tour does not run from June to October because of weather. Treat that as a single-operator signal and check the Thai Meteorological Department and the national park authority for current closure notices. Southwest monsoon swell hits exposed offshore parks hardest, so Similan and Surin are the most likely to restrict access. Shoulder months bring mixed sea conditions, so keep flexible dates. The Gulf coast follows a different pattern, which our Gulf of Thailand Islands: Which to Visit & When (Guide) page explains.

• Dry season: best odds for boats, visibility and park access.
• Monsoon: rougher seas, reduced services, possible closures.
• Shoulder months: verify weather and closure notices week by week.

How to get there and around

Fly into Phuket for the northern islands. Fly into Krabi or Trang for Lanta and the Trang islands. Pak Bara is the pier for boats to Koh Lipe. Speedboats are faster but rougher and more cancellation-prone in swell. Ferries are slower and steadier. Operator sites such as Lomprayah publish timetables where they serve your route. Check that any boat carries life jackets and a licensed crew before paying. Book onward connections with slack, because a delayed pier boat can cost you a night.

Costs, park fees and what is included

This guide has no verified fee figures for 2026. Check park entry fees and closure dates on the official national park site before you book. Ask each tour operator whether park fees, lunch and snorkel gear are included.

Choosing by trip style

Match the island to what you want from the days, not to a photo. Our ranking of the 9 Best Islands in Thailand: Pick by Coast and Trip Length helps if you are comparing coasts.

• First-timers: Phuket as a base, with day trips to Phang Nga Bay and Phi Phi.
• Families: Kata or Karon on Phuket, where services are close.
• Snorkelers and divers: Similan and Surin in season, or Lipe's Adang-Rawi stops.
• Quiet beaches: Koh Kradan, Koh Ngai, Koh Yao Noi.
• Couples: Koh Lipe or Koh Lanta.
• Budget: Koh Lanta, and skip the priciest island resorts.

Sample routes for 3, 5 and 7 days

More islands means more time on piers. Our Thailand Island Hopping: Routes, Ferries & Costs (Gulf vs Andaman) guide covers multi-island planning in more depth. One operator itinerary links Lanta, Kradan, Mook and Lipe in that order, which is a useful sequence idea.

• 3 days: Phuket base, one Phang Nga Bay day, one Phi Phi day.
• 5 days: Fly to Krabi, then Koh Lanta and Koh Kradan.
• 7 days: Lanta, then Kradan or Mook, then Koh Lipe, with one snorkel day at Adang-Rawi.

Mistakes to avoid

Booking in monsoon season is the classic error, followed by cramming too many islands into too few days. Emerald Cave on Koh Mook depends on tides. One operator describes a roughly 10 m entrance and an 80 m swim-in channel, but verify this locally. Skip unlicensed boats and unclear park-fee arrangements.

Responsible visiting

Do not stand on coral or feed fish. Keep distance from turtles and dugongs, which live in these waters. Choose operators that cap group sizes and avoid peak-hour crowding at popular stops. Follow ranger instructions inside national parks.