Similan Islands open season 2026 Tour Guide (When & Why Are the Similan Islands Closed?)

Visan Leelarapin
Aug 6
3 min read

Dreaming of powder-white sands, granite boulder formations, and crystal-clear turquoise waters teeming with marine life? The Similan Islands (Mu Ko Similan National Park) are indisputably the crown jewel of the Andaman Sea. However, if you are planning a trip to Phuket, there is one crucial detail you must know before booking your day trip: the Similan Islands are closed for five months every year.

To help you plan the ultimate Thailand vacation, the team at Phuket Travel by Zammy has compiled this comprehensive guide explaining Similan Islands open season 2026 the exact closure dates, why the shutdown takes place, and what alternative paradise islands you can explore during the closed season.

Similan Islands open season 2026

Under official regulations set by Thailand’s Department of National Parks, Wildlife and Plant Conservation (DNP), the closure schedule follows a strict annual timeline:

Official Closed Season: May 16 – October 14 every year.
Official Open Season: October 15 – May 15.

During the closed period, all tourism activities, day-trip speedboats, liveaboard dive vessels, and public access to the islands are strictly prohibited.

Why Do the Similan Islands Close Each Year?

The annual shutdown is not a hindrance; it is a vital practice that preserves the natural beauty of the archipelago for future visitors.

1. Monsoon Weather & Traveler Safety

Between mid-May and mid-October, Southern Thailand experiences the Southwest Monsoon.

Rough Open Seas: The Similan Islands sit roughly 70 kilometers off the coast of Phang Nga. During monsoon months, open-sea ocean swells, high waves, and sudden storms make the boat crossing unsafe for speedboats and catamarans.
Low Underwater Visibility: Monsoon currents churn up ocean sediment, reducing underwater visibility for snorkeling and scuba diving.

2. Environmental Regeneration & Marine Protection

Over 3,000 travelers visit the Similans daily during peak season. The 5-month rest period allows nature to bounce back:

Coral Reef Healing: Delicate coral ecosystems recover from human impact, boat anchors, and sunscreens.
Wildlife Nesting: Undisturbed beaches give green sea turtles and rare bird species a safe environment for breeding and nesting.
Park Maintenance: Park rangers use the off-season to repair floating piers, walking trails, and safety barriers across the islands.

Similan Islands Visitor Snapshot

Fact / Feature	What You Need to Know
Best Time to Book	December through March (Calmest seas & highest water clarity).
How to Get There	Hotel pick-up in Phuket $\rightarrow$ Transfer to Phang Nga pier $\rightarrow$ Speedboat ride to Similan.
Overnight Stays	Not Allowed. To protect nature, overnight stays are banned; all visits are full-day trips.
Daily Visitor Cap	Capped at 3,850 visitors/day. Advance booking is strictly required!

What If You Are Visiting Phuket Between May and October?

If your vacation falls during the Similan Islands closure, don't worry! Phuket Travel by Zammy operates exceptional year-round day trips in sheltered waters that remain calm, safe, and stunning during the monsoon season:

Phi Phi Islands & Maya Bay Tour: Explore the iconic towering limestone cliffs, swim in Pileh Lagoon, and relax on Bamboo Island.
Phang Nga Bay & James Bond Island: Cruise through sheltered emerald waters surrounded by dramatic rock formations.
Khai & Hong Islands: Ideal short boat rides for families looking for calm snorkeling waters and white sand beaches.
Phuket Jet Ski Safaris: For thrill-seekers wanting an action-packed, guided sea tour.

Book Your Island Hopping Tour with Phuket Travel by Zammy

Whether you want to witness the iconic Similan Islands during open season or embark on a Phi Phi Islands speedboat tour year-round, Phuket Travel by Zammy offers small-group and private day trips with hotel transfers, park fees, and local guides included!

Website: www.phukettravelbyzammy.com
Services: Island Hopping, Jet Ski Safaris, Elephant Sanctuaries, City Tours & Airport Transfers.