Image: Destination image
DESTINATION / THAILAND
Thailand's finest diving - granite boulders draped in soft corals with manta ray flybys
Image: Destination image
Visibility
25m
Water Temp
28C
Max Depth
35m
Current
Moderate
Difficulty
Beginner
Best Season
Nov-Dec-Jan-Feb-Mar-Apr
Certification
open water
Budget
$$ Mid-Range
Sharks
Manta Rays
Whale Sharks
Turtles
Coral
Macro
Pelagics
Dolphins
Depth: 5-35m | Intermediate
A horseshoe-shaped pinnacle rising from the deep, this is Thailand's most famous dive site with frequent manta ray and whale shark encounters.
Manta rays, whale sharks, seahorses, frogfish
Depth: 10-35m | Intermediate
Dramatic swim-throughs between massive granite boulders where currents bring schooling fish and leopard sharks.
Swim-throughs, leopard sharks, barracuda
Richelieu Rock is widely considered the best dive site in Thailand. A horseshoe-shaped pinnacle in open ocean, covered in purple and pink anemones with five species of anemonefish defending their territory — and whale sharks cruising past if luck is on your side. Dive three times and each is completely different: one dive brings a manta ray, another a massive barracuda school, another a zebra shark sleeping under a coral head. The Similans close May through October for monsoon season; liveaboards from Khao Lak are the only way to experience the best sites properly.
Best months: Nov, Dec, Jan, Feb, Mar, Apr. Peak: Jan-Feb. Water: 27-29C.
open water certification recommended. Minimum 5+ dives.
$130/day average. mid_range tier. Liveaboard: available.
Similan Islands dives best from Nov, Dec, Jan, Feb, Mar, Apr, with the peak season running Jan to Feb. During these months you can expect the calmest seas, the clearest water, and the highest chance of encountering the marine life this destination is known for. Water temperature sits at 27-29C, so a 3mm wetsuit or skinsuit is all you need in the tropics.
For divers who are flexible, the shoulder months just outside peak season offer nearly identical conditions at 20-30% lower prices and with far fewer boats on the water. The only periods to avoid are the wet or cyclone windows - check the seasonal calendar below and on the dive operator websites before locking in flights.
Visibility at Similan Islands averages 25 meters, which ranks among the clearest dive destinations in its ocean. Early morning dives consistently deliver the best visibility and the most active marine life, which is why local operators schedule most boat departures before 9am.
Getting there: Fly into Phuket (HKT). From the airport, dive operators and hotels usually arrange transfers - budget 30 minutes to several hours depending on whether your resort or liveaboard is based on the mainland, an offshore island, or a distant atoll.
Time and money: The local timezone is UTC+7. A day of guided diving averages $130 at this $$ Mid-Range tier destination. Liveaboard safaris are available for multi-day trips to remote reefs.
Who this suits: With a Beginner difficulty profile, a beginner-friendliness score of 4/5, and a minimum of 5 logged dives recommended, Similan Islands is an excellent match for newly certified divers as well as veterans. It is also family-friendly, with options for non-divers.