Thailand Islands Guide

Gulf of Thailand vs. Andaman Sea

Thailand's two coasts are different ecosystems. Gulf of Thailand (east coast: Koh Samui, Koh Phangan, Koh Tao): calm, clear, good for diving and snorkeling, gets rain in November–December. Andaman Sea (west coast: Phuket, Krabi, Koh Lanta, Koh Phi Phi): dramatic limestone karsts, turquoise water, best November–April, monsoon June–October. Both are excellent in their peak seasons.

Gulf Islands

Koh Samui

Best for: Families, couples wanting full-service resorts, first-timers who want it easy.
Vibe: Thailand's second-largest island. Developed, comfortable, resort-heavy on the north and east coasts. Chaweng Beach is the main strip — busy, lots of restaurants and bars. Lamai is slightly quieter.

Getting there: Direct flights from Bangkok (Bangkok Air has a near-monopoly — expect $60–100). Or fly to Surat Thani and ferry (longer, cheaper).

Don't miss: Big Buddha (Wat Phra Yai), Na Muang waterfalls inland, a sunset at Fisherman's Village on Bophut beach.

Koh Phangan

Best for: Party travelers (Full Moon), yoga retreats, travelers who want something between Samui and Tao.
Vibe: Famous for the Full Moon Party on Haad Rin beach (15,000–30,000 people once a month). But most of the island is nothing like that — Half Moon, Black Moon, and Jungle parties draw smaller crowds, and the northern and western beaches are genuinely quiet. Good yoga and wellness scene in Srithanu.

Getting there: Ferry from Koh Samui (30 min) or from Surat Thani pier on the mainland.

Koh Tao

Best for: Divers and snorkelers, backpackers, people who want small and social.
Vibe: Tiny island (21 sq km) with one of the world's best and cheapest dive training scenes. Open Water certification costs $350–400 and takes 3 days. The island itself is hilly, not much to do besides dive/snorkel and hang out. That's the appeal.

Getting there: Ferry from Koh Phangan (1 hour) or direct from Chumphon on the mainland.

Best dive sites: Sail Rock (whale sharks June–October), Chumphon Pinnacle, Southwest Pinnacle.

Andaman Sea Islands

Phuket

Best for: Big resort vacations, families, people who want everything in one place.
Vibe: Thailand's largest island and most developed — international airport, major resort strips, 5-star hotels, malls. Patong Beach is touristy and crowded; Kata and Karon are better. Old Phuket Town is genuinely charming with Sino-Portuguese architecture. Not the "authentic Thailand" experience but the infrastructure is undeniable.

Getting there: Direct flights from Bangkok (1 hour, $30–60) and many international cities.

Krabi / Ao Nang

Best for: Rock climbing, kayaking, day trips to islands, non-resort travelers.
Vibe: Krabi Town is the mainland hub — functional, local, cheap. Ao Nang is the beach strip — more tourist-oriented but less overwhelming than Patong. The real draw is the water and limestone karsts. Railay Beach (accessible only by longtail boat) is spectacular.

Day trips: Four Islands tour, Hong Islands, Phi Phi Islands (day trip or overnight).

Koh Phi Phi

Best for: The Instagram shot (Maya Bay), snorkeling, travelers who don't mind crowds.
Vibe: Tiny, beautiful, famous from "The Beach." No cars, everything on foot or by boat. Maya Bay (the movie beach) reopened after 3-year closure for reef restoration. Stunning — and now it has timed entry tickets and a crowd limit. Do it early. Phi Phi Don village is chaotic and bar-heavy at night.

Getting there: Ferry from Phuket (90 min) or Krabi (60 min). Day trip or stay on the island.

Koh Lanta

Best for: Families, couples, digital nomads, longer stays, quieter vibe.
Vibe: Long, forested island with a series of beaches down the west coast — Klong Dao (calm, good for kids), Long Beach, Klong Nin (best restaurants), Kantiang Bay (dramatic, remote). Slower pace than Phi Phi or Patong. Old Town on the east coast is worth a morning wander.

Getting there: Ferry from Krabi or Phuket. 1.5–3 hours depending on route.

Island-Hopping Tips

• Don't try to do more than 2–3 islands in 10 days — ferry time adds up fast
• Book ferries at 7-Eleven, your guesthouse, or Lomprayah/Seatran Discovery online
• Travel light: island-hopping with a wheeled suitcase is painful. Use a backpack or soft bag.
• The combo ticket (e.g., Bangkok → Koh Samui → Koh Phangan → Koh Tao in one booking) is usually cheaper than buying each leg separately
• Check weather on both coasts before booking — don't hit the Andaman during monsoon if you want beach days

Quick Comparison

• Most developed / easiest: Phuket, Koh Samui
• Best diving: Koh Tao, Koh Lanta, Similan Islands (live-aboard)
• Most Instagram-famous: Koh Phi Phi (Maya Bay), Railay Beach
• Quietest / most local: Koh Lanta, Koh Yao Noi, Koh Libong
• Best for Full Moon Party: Koh Phangan (obviously)
• Best for families: Koh Lanta, Koh Samui (Bophut)

Gear We Recommend for Thailand

Eight travel essentials that make a Thailand trip smoother — from lightweight daypacks to reef-safe sunscreen that won't get confiscated at the temple.

Related Reading

• Thailand Travel Guide (Pillar)
• Bangkok Travel Guide
• Chiang Mai Travel Guide
• Thailand on a Budget