Suthep Bay - Similan Islands

Suthep Bay, tucked into the eastern side of Similan Island #4, is one of those places that feels surprisingly calm, even when other sites are buzzing. We love dropping in here, especially first thing in the morning. The gentle slopes are covered in fields of staghorn coral, just stretching out as far as you can see, almost hypnotic in their rhythm. You’ll spot a lot of parrotfish here, the big dusky ones and the bright saddled varieties, munching away. Keep an eye out for the blue-spot blennies popping their heads out of the sand, they’re always a fun find. The silversides, though, are our favourite – sometimes the schools are so dense they shimmer like a liquid wall, then part to reveal a slender maori wrasse cruising through. It’s a beautifully relaxed dive, perfect for photographers wanting to take their time or for divers who just want to soak in the sheer scale of the coral.

Location
Similan Islands, Thailand, Southeast Asia
Coordinates
9.415387, 97.848810
Type
reef

Marine Protected Area: Muko Surin

Best Time to Dive in Similan Islands

The warmest water temperatures in Similan Islands occur in May, averaging 30.8°C. The coolest conditions are in January at 28.6°C.

Monthly Water Temperatures

  • January: 28.6°C
  • February: 29.0°C
  • March: 29.6°C
  • April: 30.6°C
  • May: 30.8°C
  • June: 29.9°C
  • July: 29.6°C
  • August: 29.3°C
  • September: 29.0°C
  • October: 29.0°C
  • November: 29.2°C
  • December: 28.7°C

Nearby Dive Sites in Similan Islands

Nearest Dive Centres to Suthep Bay

Marine Life in Similan Islands

Home to 183 recorded species including 127 reef fish, 38 hard corals, 9 seagrass & algae, 4 sharks & rays, 2 other, 1 octopus & squid.

Notable Species

Recommended Packing List for Suthep Bay

Based on average water temperature of 29.4°C, currents 7 cm/s.

  • Shorty or Rashguard - warm 29°C water needs minimal exposure protection
  • Mask - essential for every dive
  • Fins
  • BCD - buoyancy compensator
  • Regulator - your most safety-critical piece of gear
  • Dive Computer - tracks depth, time, and NDL
  • Surface Marker Buoy (SMB) - essential for boat pickups
  • Dive Torch - useful for crevices and colour at depth
  • Underwater Camera - capture your diving memories