Khao Lak vs Phuket: Which Base for Diving the Similans?

by Yannick SchrothOct 13, 202610 min read

Richelieu Rock breaking the surface at low tide, in Mu Ko Surin National Park. Photo: Mr.CMBurns, Wikimedia Commons, CC BY-SA 4.0.

The 2026/27 Similan season from Khao Lak and Phuket: 15 October to 15 May

Mu Ko Similan National Park reopens on 15 October 2026. The Department of National Parks gives its season as 15 October to 15 May every year, and its own news service reported the park closed from 16 May 2026 to let its reefs and forest recover. Mu Ko Surin, the park that holds Richelieu Rock, sits on the same calendar in the Tourism Authority of Thailand's listing: closed 16 May to 14 October. Some press reports put the 2026 closure a day earlier at each end, so for the first and last week of a season, confirm with the boat before you pay.

That calendar matters more to Khao Lak than to Phuket. Both parks are in Phang Nga province, and they are what Khao Lak's dive boats are for. Phuket has reefs of its own on the other side of the season. As of October 2026, the comparison looks like this:

Most Similan boats leave from Thap Lamu, near Khao Lak, not from Phuket

The park office is on the mainland in Thap Lamu village, and that is where the boats go from. Sunrise Divers, a Phuket shop that sells boats from both places, writes that most Similan liveaboards now depart from Thap Lamu and that only some still sail from Chalong Bay or Patong Bay in Phuket, some of them adding Phi Phi or Hin Daeng and Hin Muang on the way. Boats leaving from Khao Lak mostly include a free transfer from Phuket hotels. On a liveaboard, then, where you sleep the night before costs you an afternoon in a minibus and nothing more.

Day trips are where the base shows. Thailand Divers, which runs Similan speedboat days from Thap Lamu, collects Phuket guests between 05:30 and 06:40 and Khao Lak guests around 07:00, for a 09:00 departure and a return to the pier between 17:00 and 17:30. From Phuket the drive back comes after that. By those pickup times, every Similan day from Phuket adds two to three hours in a minivan.

The drive itself is short from the airport and long from the beaches. Phuket International Airport to Khao Lak takes about an hour to an hour and a half by road, roughly 75 km, depending on the hotel. That range is triangulated from independent hotel and travel listings rather than an official figure. From the south of Phuket, Sunrise Divers puts the minibus at about two hours.

Richelieu Rock is a day trip from Khao Lak and a liveaboard from Phuket

Richelieu Rock is a pinnacle in Mu Ko Surin National Park, further up the Phang Nga coast; Sunrise Divers puts the Surin islands about 100 km north of the Similans. Several Khao Lak shops sell it as a day trip by speedboat. Sea Bees runs two dives from Thap Lamu, November to April, and recommends Advanced Open Water. Sunrise Divers' Blue Dolphin leaves from Nam Khem pier, north of Khao Lak, at 09:00 and puts the ride to its sites at about an hour, from about 10 November to 10 April. Similan Seven Sea Club lists a two-dive day with pickups in Khao Lak and Bang Niang.

None of them collects from Phuket. Sunrise tells guests staying there to get to Khao Lak or the pier by 09:00 on their own. From Phuket, then, Richelieu Rock means a liveaboard on one of the northern routes that add Koh Bon and the rock to the Similans.

Notice the day-trip window. The parks open on 15 October, but the Richelieu day boats in those listings run from November to April. In late October and early May, plan on a liveaboard for it from either base. One more thing changed this year: in July 2026 the department opened a public consultation on the Surin park boundary, because the map attached to the founding decree does not cover the whole of Richelieu Rock. The consultation notice says nothing about access for divers.

Similan park rules that apply whether you base in Khao Lak or Phuket

Nobody sleeps on the Similans. Overnight stays in the park were closed by a department announcement dated 4 October 2018, published in the Royal Gazette four days later, which made the islands one-day trips only. In August 2026 the department opened an inquiry into its own park chief over a group allowed to stay about four years earlier. So the choice really is a bed in Khao Lak, a bed in Phuket or a bunk on a boat.

Divers are capped. The last daily cap the park itself published, in October 2021, was 3,850 visitors a day, 525 of them divers. The Tourism Authority listed the same 525 dive places in 2019. Whether that figure still stands for 2026/27 is a question for your operator.

Koh Tachai is still a question mark. The island has been closed since 15 May 2016, and the Tourism Authority's listing extends that to its beach and coral reef. In April 2025 the department said it was preparing a reopening but had set no date. If an itinerary lists a Tachai dive, ask what exactly is permitted this season before you choose a boat for that dive.

What Phuket dives while the Similans and Surin are shut

This is Phuket's half of the argument. Its day boats leave Chalong pier around 08:00 to 08:30 and are back by about 17:00 to 18:00. The usual destinations are Racha Yai and Racha Noi to the south, and to the east Shark Point, Anemone Reef, Koh Doc Mai and the King Cruiser, a sunken passenger ferry, often combined with Phi Phi. Racha Noi is about two hours out: Sunrise Divers leaves Chalong at 08:30 and arrives at 10:30.

These trips do not stop in May. Sunrise runs its Racha Noi day “every day in the high season and pretty much every day in low season too”, and from June to September offers shorter liveaboards to Phi Phi and Racha in place of the Similans. Expect the low-season days to depend on wind and swell.

Racha Yai is also busy. In August 2026 the Department of Marine and Coastal Resources reported crowded moorings and buoy problems at its Patok Bay, and the national parks and marine departments picked Racha Yai and Phi Phi as the first areas for new tour-boat standards, with Surin next. If a quiet reef matters to you, ask which side of the island the boat will use.

The recompression chamber for Khao Lak and Phuket is on Phuket

The chamber for this coast is SSS Phuket, at Bangkok Hospital Siriroj. It opened in 1996, takes up to four people including the inside attendant, can be pressurized to 50 meters, and says it serves the entire west coast of Thailand. Its 24-hour emergency line is 081-0819000, as listed by the hospital in October 2026.

From a Phuket hotel that is a short drive. From Khao Lak it is the road back toward the airport and beyond, and from the Similans or Richelieu Rock it is a boat ride to the pier first. That is not a reason to avoid Khao Lak. It is a reason to check that your dive insurance pays for the evacuation as well as the treatment, and to ask the boat what its emergency plan is.

How much choice Khao Lak and Phuket give you in dive shops

Against all that, the operator lists. They settle none of the above; they show how big each market is.

Sixty against eight measures the towns more than the Similans. The liveaboards are largely the same boats from the same pier, and Phuket shops sell them with a minibus attached. Phuket's eight Green Fins members were all assessed in person within the twelve months before the register was read in August 2026; that scheme is about environmental practice rather than safety.

Khao Lak for a Similan winter, Phuket for a longer stay

Base in Khao Lak if your dates sit between November and April and the Similans, Koh Bon or Richelieu Rock are the point. Your day-trip pickup comes up to 90 minutes later, and Richelieu is reachable without a liveaboard. The Khao Lak and Similan guide covers liveaboard lengths and costs, and the Khao Lak operator list has the eight registered shops. It is the wrong base from mid-May to mid-October.

Base in Phuket if you are staying for months, working between dives, or arriving after the parks close. Liveaboards will collect you anyway, and the airport and the chamber are on the island. What it costs you is early starts for Similan day trips and no Richelieu day trip at all. Diving from Phuket has its Green Fins members, and for a stay of a season or more the Thai DTV is the visa to read about. If Krabi is the third option on your list, Phuket vs Krabi sets out the closures on that side of the bay.