10 Best Secret Islands in Thailand

Koh Lipe (also spelt Koh Lipeh or Koh Lipey) is a small paradise island right next to the Tarutao National Marine Park, near the border with Malaysia in southern Thailand. It's famous for its 3 pristine beaches, Sunset Beach, Sunrise Beach, and Pattaya Beach. While Koh Lipe hosts a fair amount of accommodation choices, it’s still relatively unknown. 

You can enjoy a relaxing holiday far from the crowds, while enjoying activities like snorkelling, scuba diving, and island-hopping. Koh Lipe is well served by ferries and speedboats from Pak Bara (Satun Province), Phi Phi, Koh Lanta, and Trang during the high season (December–April). However, the island can only be reached by speedboat from Pak Bara in the low season.

Koh Phayam is the most popular island in the province of Ranong. Located 200 km north of Khao Lak, it's a great getaway for those looking for an off-the-beaten-track destination in Thailand. Featuring 2 main beaches, Ao Yai (Long Bay) to the southwest and Ao Khao Kwai (Buffalo Bay) to the northwest, this 50-sq-km island has only around 500 residents. It offers a travel-back-in-time experience. 

There are no cars on Koh Phayam, so the only way to travel around is by renting a motorbike or bicycle. A few narrow cement roads allow people to easily reach the main bays and tips of the island from Koh Phayam Pier (on the east coast). The central part of Koh Phayam is rather flat, hosting cashew tree plantations and virgin forests. A large patch of mangrove forest can be found at the western end of Buffalo Bay, offering a wild playground to sea kayakers.

Koh Mak is around 35 km off the coast of Trat Province on the eastern side of the Gulf of Thailand. This 16-sq-km island has a picturesque shoreline spanning 27 km, with splendid white sand beaches, coconut groves and mangrove forests.

Koh Mak hosts a good range of accommodation for all types of budget. Sea kayaking and snorkelling are the favourite activities on the island. At low tide, you can walk to Koh Kham, an islet just 1 km off the northwestern tip of Koh Mak. Despite its development in tourism, Koh Mak retains a strong and pleasant local vibe.

Koh Tarutao is just north of Langkawi Island in Malaysia. The island lends its name to a national park which counts no less than 51 islands. Around 70% of the island is covered by thick rainforest, making it a great place for outdoor activities. 

Koh Tarutao used to be a penal colony between 1938 and 1948. The national park headquarters offers 2 types of accommodation: bungalows and tents. The island’s most beautiful beaches are on the west coast. The east coast has lush mangrove forests. Birdwatching, hiking, and snorkelling are the main activities on the island. Ferries and speedboats link Koh Tarutao to Pak Bara and Koh Lipe.

Koh Ngai (or Koh Hai) in Krabi is great for nature lovers in Thailand. The island has some great coral reefs along its coastline, making it popular for snorkelling. It's under the supervision of Mu Koh Lanta National Park. Expect plenty of big and small beaches with gorgeous views of tiny karst islands and some equally well-known nearby islands, including Koh Libong, Koh Mook, and Koh Lanta. 

Koh Ngai has a handful of beach accommodations, some of which have swimming pools. Outside guests can make use of the facilities if they dine at onsite restaurants or bars.

Koh Phra Thong ('Golden Buddha Island' in Thai) is an 88-sq-km island about 40 km north of Khao Lak. As with most islands in Phang Nga and Ranong, it has mangrove forests to its eastern coast and white-sand beaches and rocky islets to its western coast.

The central area of the island has all the characteristics of an African savanna – you’d almost expect to see zebras, giraffes and lions wandering around! Koh Phra Thong counts only a few accommodation choices. Most hotels on the west coast are budget or mid-range bamboo-and-thatch bungalows.

Koh Mook lies between Krabi and Trang in the Andaman region. Rumour has it that it was here, at Emerald Cave, where pirates hid their treasure. The place was known only a few decades ago, accidentally found by locals searching for bird’s nests (a delicacy in Chinese cuisine). 

Koh Mook (also spelt Koh Muk) has subsequently been ‘discovered’ by paradise seekers from all over the world. A handful of accommodation options are on the island. Many are on Haad Farang Beach, operating only during the high season (November–April). A few of them stay open year-round, great for those who prefer to visit in the low season. Most Koh Mook hotels are in the budget to mid-range category, meaning you can choose from a basic bamboo chalet with the fan to a comfortable bungalow with air-conditioning.

Koh Kho Khao offers an off-the-beaten-track getaway for families in Thailand. The island is a short boat ride from Takua Pa, just north of Khao Lak. Its main attraction is a 14-km-long beach that might remind you of the long strips of sand in Khao Lak. 

While the island is barely developed, it still hosts a decent choice of hotels and resorts. You can rent a motorbike to explore the different areas of the island, which include mangrove forests, an overgrown airstrip used by the Japanese during WWII, and an archaeological site. Sea kayaking is a popular activity on Koh Kho Khao, but there’s also a dive centre offering diving and snorkelling trips to nearby sites, and further west, to the Similan Islands.

Koh Bulon Leh is excellent for those looking for an authentic island experience in southern Thailand. A few lowkey bungalows and only one modern resort are on the island. Note that only the resort has 24/7 electricity, while other accommodations rely on a generator that runs at night. 

A holiday on Koh Bulon Leh is truly an experience as it seems like progress has not yet reached the coast of this little pristine island. The inhabitants are chao leh (sea gypsies), who carefully maintain the island’s natural beauty. The crystal-clear water surrounding Koh Bulon Leh hosts impressive marine life. Snorkelling, sea kayaking, and hiking are the main activities on the 3-sq-km island. You can explore it on foot, hopping from one beach to the other.