Similan Islands Closed For the Low Season

The Similan Islands, a jewel in the Andaman Sea off the coast of Thailand, are renowned for their stunning natural beauty, crystal-clear waters, and vibrant marine life. Comprising nine primary islands and two far-flung outliers, this region has long been a major attraction for divers, snorkelers, and beach lovers from around the world. However, there’s something crucial for every would-be visitor to know: the Similan Islands are closed to the public from May through October each year. This seasonal closure, though it may seem inconvenient to travellers, is vital for the preservation of this pristine environment.

A Seasonal Sanctuary

So, why exactly do the Similan Islands close for half the year? The answer lies in a combination of environmental protection and safety concerns. The monsoon season, which hits this region from May to October, brings heavy rains, strong winds, and rough seas, making it hazardous for travel and water activities. By closing the islands during this period, authorities aim to protect both visitors and the delicate ecosystems that thrive here.

Protecting Marine Life

One of the primary reasons for the seasonal closure is to give the marine environment a much-needed break from human traffic. The Similan Islands are part of a national park, and their waters are teeming with life, including colourful coral reefs, diverse fish species, and even larger creatures like manta rays and whale sharks. Constant tourism can put immense pressure on these ecosystems, leading to coral bleaching, pollution, and disruption of marine life.

During the closure, marine life can recover and thrive without the disturbance of boats, divers, and snorkelers. Coral reefs, which are particularly sensitive to human impact, have a chance to regenerate and strengthen. This break also helps maintain the high biodiversity that the Similan Islands are famous for, ensuring that when the islands reopen, they remain a vibrant and enchanting destination.

Rejuvenation of Vegetation

It’s not just the underwater world that benefits from the closure. The islands themselves, with their lush forests and pristine beaches, also need time to recover. Foot traffic on trails, litter on beaches, and the presence of humans can all take a toll on these environments. The closure period allows vegetation to regrow, wildlife to roam undisturbed, and beaches to remain clean and natural.

Ensuring Visitor Safety

Safety is another critical factor in the decision to close the Similan Islands during the monsoon season. The weather conditions from May to October can be unpredictable and often severe. High winds, heavy rains, and turbulent seas make boating and other water activities extremely dangerous. By closing the islands, authorities can prevent accidents and ensure that when visitors do come, they can enjoy their experience in a safe and controlled environment.

Sustainable Tourism

The seasonal closure of the Similan Islands is a shining example of sustainable tourism in action. By managing visitor numbers and allowing natural environments to recover, Thailand is ensuring that these islands remain a viable and beautiful destination for years to come. This approach balances the needs of tourism with environmental conservation, setting a standard for other destinations facing similar challenges.

What Visitors Can Expect Upon Re-opening

For those planning a trip to the Similan Islands, it’s essential to keep the closure dates in mind. The islands typically close at the beginning of May and reopen at the beginning of November. This timing can vary slightly depending on weather conditions and environmental assessments, so it’s always a good idea to check for the latest updates before making travel plans.

When the islands are open, visitors can expect a truly magical experience. From diving into the vibrant underwater world to hiking through lush forests and relaxing on pristine beaches, the Similan Islands offer something for every nature lover. Dive sites like Richelieu Rock and Elephant Head Rock are famous for their stunning coral formations and diverse marine life, making them must-visit spots for any diving enthusiast.

How to Visit Responsibly

To help preserve the beauty of the Similan Islands, visitors should follow a few simple guidelines:

  1. Respect the Environment: Avoid touching or stepping on corals, and do not disturb marine life. Take only pictures and leave only footprints.
  2. Follow Regulations: Adhere to all park rules and regulations, including those regarding waste disposal and protected areas.
  3. Use Reef-Safe Products: Opt for sunscreen and other products that are safe for marine life to minimize your impact on the underwater environment.
  4. Support Sustainable Practices: Choose tour operators and accommodations that prioritize sustainability and environmental protection.

The Future of the Similan Islands

The seasonal closure of the Similan Islands highlights a broader commitment to preserving Thailand’s natural heritage. By protecting these islands and their ecosystems, Thailand is not only safeguarding its environmental treasures but also ensuring that future generations can enjoy them. This approach to conservation sets an example for other countries and destinations around the world, demonstrating that sustainable tourism is both possible and necessary.

Does Simba Visit the Similan Islands? 

Simba Sea Trips offers a Similan Islands Tour by Speedboat once the region re-opens to tourism from November to early May each year. This incredible tour is a favourite of our guests due to the early departure time and lower guest numbers which makes the trip more luxurious and comfortable than most other tours operated to the region. 


The seasonal closure of the Similan Islands from May through October is a vital measure for protecting and preserving this beautiful part of the world. While it may require some adjustments to travel plans, it ensures that the islands remain a pristine and magical destination for future visitors. By understanding and supporting these efforts, travellers can contribute to the ongoing conservation of the Similan Islands and enjoy a truly unforgettable experience when they visit.

So, mark your calendars, plan your trip with Simba for November, and get ready to explore the breathtaking beauty of the Similan Islands – a place where nature thrives and adventure awaits!