Phuket vs Krabi: Which Is Better for Diving?

by Yannick SchrothSep 5, 20267 min read

Koh Phi Phi, in Krabi province, one side of this comparison. Photo: Caitriana Nicholson, Wikimedia Commons, CC BY-SA 2.0.

The closures that set your dates

Thailand shuts marine national parks on a published schedule, and the four that matter here close on four different dates. This is the part worth checking before you book anything, because it is the part that cancels trips.

One caveat on Hin Daeng. The dates above are the Tourism Authority's. Other published schedules give the Mu Ko Lanta closure as 16 May to 14 October, and Ko Rok separately as 1 June to 30 September. That is not resolved against a current announcement from the park itself, so treat July to September as certain and the shoulders as worth a phone call.

Phuket's own day sites are on none of those lists. Racha Yai and Racha Noi to the south, and the King Cruiser wreck, Shark Point, Anemone Reef and Koh Doc Mai to the east, stay open through the southwest monsoon. What they lose is visibility rather than access: operators there run the sheltered east side of Racha Yai from May to September, and describe the eastern wreck sites as a dry-season proposition.

Koh Lanta is a six-month island

This is the fact that decides it for anyone working while they dive, and it is in no dive guide. KoHub, the island's coworking space, publishes its own season: open 1 November to 30 April, closed May to October. Its page on the seasons says about 80% of the island's businesses close in low season, and that “all the boat/island trips also finish”.

So a Lanta winter is one of the better arrangements in Thailand, dive in the morning, work in the afternoon, on an island small enough to cycle across. A Lanta summer is not a working base at all. Phuket has no equivalent gap: the airport, the shops and the boats run through the monsoon, and what changes is which side of the island you dive.

The nearest chamber is on Phuket

The SSS Hyperbaric Chamber Network runs two recompression chambers in Thailand: one on Koh Tao and one on Phuket. There is no third on the Andaman side. The Phuket chamber is a multiplace unit at 44/1 Moo 5, Chalermprakiat Ror 9, Vichit; it takes up to four occupants including an inside attendant, is rated to 50 metres, and its operator describes it as serving the entire west coast of Thailand from the Myanmar border to Malaysia.

From Koh Lanta or Phi Phi that means a boat and then a road. It is not a reason to avoid either island. It is a reason to know what your insurance covers for evacuation, and to ask the shop what their plan is, before you are the one asking from the boat.

Getting there, and getting out

Phuket handled around 17.4 million passengers in 2025, roughly 10 million of them international. Krabi handled about 3.1 million, of which some 760,000 were international. The shape of the schedules matters more than the totals. Krabi's long-haul is largely seasonal charter, Finnair from Helsinki, TUI fly Nordic from Gothenburg and Oslo, SAS from Copenhagen from December 2026, on top of year-round regional links to Kuala Lumpur, Singapore, Dubai and Sharjah. Several of those do not fly in the months the parks are shut. Phuket's long-haul runs all year.

What the operator registers add for Phuket and Krabi

Against that, the compiled counts. They settle none of the above; they tell you how much choice each side gives you, and how much of it anybody has actually looked at.

Green Fins publishes membership at levels that mean different things. A Certified member was assessed in person against a published standard within the last twelve months. A Digital Member filled in a self-evaluation and nobody visited. It is about environmental practice rather than safety, and a centre outside it may run a tighter boat than one inside it.

Six of Koh Lanta's thirteen have been assessed in person, against eight of Phuket's sixty-one. Both are small numbers. The practical reading is that on Lanta you can pick an assessed shop without much effort, and on Phuket you would have to go looking.

One thing the counts hide: “Krabi” is a province, and its diving is not in Krabi town. Thirteen centres are on Koh Lanta, six on Koh Phi Phi, and one between Krabi town and Ao Nang. Both islands are a ferry from the mainland, which is worth knowing when a trip is sold to you as diving in Krabi.

Phuket or Krabi: which to pick

Phuket if your dates fall outside November to April, if you want the Similan liveaboards, or if you would rather be an hour from the chamber than a boat ride. Koh Lanta for a winter: quieter diving, an assessed shop within easy reach, and somewhere to work between dives, but only from November, and out by May. Koh Phi Phi if you want to be on the island the boats visit rather than on the boat visiting it, and are relaxed about the fact that none of its six centres has been assessed.