Can I charter in Phuket in July?

Yes, in Phang Nga Bay, at low-season rates and with a flexible itinerary. What you cannot do is go to the Similans, the Surins, Koh Haa or Koh Rok, because those parks are closed by order, or reliably cross to Phi Phi.

When exactly do the national parks reopen?

Mu Ko Similan and Mu Ko Surin reopen on 15 October and close on 16 May. Mu Ko Lanta runs a similar mid-October to mid-May pattern. Dates are set annually and the park authority can extend a closure.

Is the diving better in a particular month?

Visibility is best from December to April across the region. Manta and whale shark sightings at Racha Noi and in the Similans cluster from February to April, though nobody can promise them.

Cruising grounds and weather

Northeast against southwest monsoon, and what each one closes

When is the best time to charter a yacht in Phuket?

The short answer

When is the best time to charter a yacht in Phuket?

The northeast monsoon runs from November to April and is the only practical charter season on the Andaman coast: dry, 10 to 15 knots, flat seas and 28 to 32 degrees, with December to February as the settled core. The southwest monsoon runs from May to October, bringing swell onto the whole west coast of Phuket and closing the Similan, Surin and Lanta national parks by order from mid-May to mid-October. Charter is still possible in the green season, but only in Phang Nga Bay, which sits in the wind shadow of Phuket itself.

Two winds, one island in the way

Thailand's Andaman coast has a monsoon climate, which means the wind reverses twice a year rather than blowing from a prevailing direction. From November the northeast monsoon comes off the Asian landmass: dry air, moderate breeze, settled sea. From May the southwest monsoon comes off the Indian Ocean with two thousand miles of fetch behind it, and everything on the west side of Phuket takes it directly.

The single most useful fact about Phuket cruising follows from that geometry. Phuket is a substantial island lying north to south, and Phang Nga Bay is behind it. In the southwest monsoon the island is the breakwater, and the bay behind it stays workable when the coast in front of it does not.

The northeast season, November to April

Month	Conditions	Note
November	The season sets in, close to peak	Fleet returns, prices not yet at peak
December	Excellent	Christmas and New Year carry a premium and a minimum length
January	The best of the year	10 to 15 knots, flat, best visibility
February	Peak	Manta season begins at Racha Noi
March	Peak, warmer	Similan moorings at their busiest
April	Hot, still settled	Over 33 degrees. Departing yachts sometimes discount

The southwest season, May to October

The rain is not the problem people expect. It arrives in heavy squalls of an hour or two rather than as continuous drizzle, and a green-season day frequently has more usable sunshine than a February day in Europe. The problems are swell and closures.

Swell on the west and south. The crossings to Phi Phi and the Rachas become uncomfortable, and the Krabi anchorages, which are open to the west, stop being tenable.
Park closures. Mu Ko Similan and Mu Ko Surin close from 16 May to 14 October by order. Mu Ko Lanta closes over roughly the same window, taking Koh Haa and Koh Rok. Maya Bay closes separately from 1 August to 30 September.
September. The wettest month in Phuket. If the dates are fixed and September is one of them, the Gulf of Thailand is a better answer than the Andaman.

Where you can still sail from May to October

Phang Nga Bay, and specifically the eastern anchorages and Koh Yao. The bay is in the lee, the limestone is still limestone, the caves do not care about the weather because they care about the tide, and the anchorages that are packed in February can be empty on a June weekday.

The anchorage side changes, which is the piece nobody explains. In the northeast season you anchor on the east and south sides of an island. In the southwest you use the west-coast anchorages at Koh Yao, which are exposed in high season and sheltered in low. It is the same cruising ground read backwards.

Green-season charter is real, cheaper and almost empty, and it is not for a group whose one week of the year has to work. It is excellent for anyone flexible about the day-to-day plan.

The other coast

The Gulf of Thailand, on the eastern side of the peninsula, runs on the opposite cycle: good from roughly January to September, with its wet season in November and December. It is a different cruising ground with a different character and it is the honest answer to a July charter in Thailand.

Questions people also ask

Can I charter in Phuket in July?: Yes, in Phang Nga Bay, at low-season rates and with a flexible itinerary. What you cannot do is go to the Similans, the Surins, Koh Haa or Koh Rok, because those parks are closed by order, or reliably cross to Phi Phi.
When exactly do the national parks reopen?: Mu Ko Similan and Mu Ko Surin reopen on 15 October and close on 16 May. Mu Ko Lanta runs a similar mid-October to mid-May pattern. Dates are set annually and the park authority can extend a closure.
Is the diving better in a particular month?: Visibility is best from December to April across the region. Manta and whale shark sightings at Racha Noi and in the Similans cluster from February to April, though nobody can promise them.

Last checked 6 September 2026. Rates, fees and regulations in this market change every season, so figures on this page are correct as at that date and not afterwards. How the figures are gathered.