Similan Islands Guide: Snorkeling Paradise

Introduction to the Similan Islands

The Similan Islands are a group of eleven islands in the Andaman Sea, located about 70 kilometers northwest of Phuket. They are part of the Mu Ko Similan National Park and are widely regarded as one of the top snorkeling and diving destinations in all of Southeast Asia. The name "Similan" comes from the Malay word "sembilan" meaning nine, referring to the original nine islands in the group.

What makes the Similans special is the exceptional water clarity, which often exceeds 25 meters of visibility, and the healthy coral reefs that support an incredible variety of marine life. The islands are uninhabited (aside from national park ranger stations) and have been carefully protected, resulting in a pristine natural environment.

When Are the Similan Islands Open?

This is crucial information for planning your trip. The Similan Islands are only open from approximately October 15 to May 15 each year. The exact dates vary slightly from year to year based on weather conditions and park authority decisions. During the monsoon season (May to October), the islands are completely closed to visitors and all boats. No tours operate during this period.

The best conditions are typically from January through April, when the sea is calmest and visibility is at its peak. December is also excellent. November and early May can be slightly rougher but still offer good snorkeling conditions. For more details on the season, see our article on when the Similan Islands open and close.

How to Get to the Similan Islands from Phuket

Day trips to the Similan Islands from Phuket are a full day affair. Here is how it works:

1. Hotel pickup: You are collected from your hotel in Phuket early in the morning, typically between 5:30 and 6:30 AM.
2. Transfer to pier: A minivan takes you to Tap Lamu Pier in Phang Nga province, about 1.5 hours north of Phuket.
3. Speedboat to islands: From the pier, a speedboat ride of about 60 to 70 minutes brings you to the first island.
4. Island hopping: You spend the day visiting 3 to 5 islands, with snorkeling stops, beach time, and lunch.
5. Return: The boat heads back to the pier in the afternoon, and you are transferred back to your hotel, arriving around 6:00 to 7:00 PM.

It is a long day (12+ hours door to door) but the effort is well worth it for the quality of snorkeling.

Best Snorkeling Spots in the Similans

Island 4 (Koh Miang)

The main island with park headquarters, a small beach, and good snorkeling right off the shore. You will often see colorful reef fish, small sharks, and sea turtles in the shallow coral gardens.

Island 8 (Koh Similan)

The largest island in the group, known for the famous Sail Rock (also called Balance Rock), a massive boulder perched on a hillside. The snorkeling here is excellent, with healthy hard corals and abundant fish life. You can also climb to the viewpoint for a panoramic view of the surrounding islands.

Island 9 (Koh Ba Ngu)

Features dramatic underwater granite boulders that create swim-throughs and overhangs. The contrast between the white granite and colorful soft corals makes this a favorite spot for underwater photography.

Christmas Point

Located at the northern end of Island 9, Christmas Point has spectacular underwater rock formations covered in soft corals. This is a top dive site but also offers excellent snorkeling in the shallower areas.

Marine Life You May See

The Similan Islands are home to an extraordinary range of marine species. While snorkeling, you have a good chance of spotting:

• Hawksbill and green sea turtles
• Blacktip reef sharks
• Leopard sharks (resting on the sandy bottom)
• Giant clams
• Clownfish in their anemone homes
• Parrotfish, angelfish, butterflyfish, and triggerfish
• Moray eels hiding in reef crevices
• Schools of fusiliers and jacks
• Octopus (if you look carefully)

If you are lucky, you might even encounter a manta ray, though these are more commonly seen while diving at deeper sites.

Costs

• Group speedboat day trip from Phuket: 2,500 to 4,500 THB per person
• National park entrance fee: 500 THB for foreign adults, 300 THB for children (often included in tour price)
• Liveaboard diving trips: 15,000 to 30,000 THB for 2 to 4 nights

Most day trips include breakfast, lunch, fruit, drinking water, snorkeling equipment, life jackets, and round-trip hotel transfers from Phuket.

Tips for Your Similan Islands Trip

• Use reef-safe sunscreen only. The park is strict about protecting the reefs.
• Take motion sickness medication if you are prone to seasickness. The open ocean crossing can be rough.
• Bring a waterproof camera. The underwater visibility makes this a dream for photos.
• Wear a rash guard. It protects against sun and jellyfish stings.
• Book in advance during peak season (December to March). Tours fill up quickly.
• No overnight stays are currently allowed on the islands. All camping has been suspended to aid conservation.

The Similan Islands represent the gold standard for snorkeling in Thailand. If you visit Phuket between November and May, this should be at the top of your list. Browse our available tours to find the right Similan Islands trip for you.