Similan Islands Diving & Snorkeling Day Trips from Khao Lak

The Similan Islands rank among Asia’s top ten dive destinations on most serious lists, and justifiably so. Eleven granite islands sit in the Andaman Sea roughly 65 km northwest of Khao Lak, surrounded by visibility that regularly reaches 20–30 metres and a reef system healthy enough to support whale sharks, manta rays, leopard sharks, and thousands of reef fish. This guide covers day trip options, scuba versus snorkeling, what operators charge, and the logistics of making it work.

How to get there

All day trips depart from Tap Lamu Pier, about 10 km south of Khao Lak town. Most operators run shared speedboats holding 25–40 passengers; the crossing takes approximately 1.5 hours each way. A handful of operators run slower wooden long-tail vessels on the same route, but speedboats dominate the day-trip market and are the practical choice.

From Phuket, Khao Lak is roughly 80 km north - about 90 minutes by road. If you’re based in Phuket and want to day-trip the Similans, it is physically possible but long: the combined travel time (Phuket → Khao Lak pier → islands → return) makes for a 12–13 hour day. Staying overnight in Khao Lak and doing the trip from there is the smarter approach.

Snorkeling day trips

The most popular format. Operators load guests onto speedboats for the 1.5-hour crossing, then spend 5–6 hours moving between 3–5 snorkeling stops across different islands. Most trips hit Island 4 (Ko Miang) - the park’s HQ island with calm bays and good shallow coral - and Island 8 (Ko Similan), which has the famous “Rock” granite boulder formations on its west side and a viewpoint worth the 30-minute hike.

What’s included in a typical snorkeling day trip:

• Return speedboat transfer from Tap Lamu Pier
• National park entrance fee (approximately THB 500 as of 2026, foreigners; approximately THB 100 for Thai nationals - confirm with your operator as this changes periodically)
• Snorkel mask, fins, and life jacket
• Lunch (usually a Thai buffet on the boat or at the park canteen)
• Drinking water and fruit

Price range: THB 2,800–3,500 per person as of 2026. Operators to compare: Sea Dragon Dive Center, Khao Lak Seafan Dive Center, and Bob’s Kite & Dive are all established names with multi-year track records. Booking through GetYourGuide’s Similan Islands listings lets you compare current availability and read recent reviews in one place.

Scuba diving day trips

For certified divers, the Similans deliver. Key sites include:

Elephant Head Rock (Ko Similan) - The signature dive. A cluster of massive granite boulders between 5 and 30 metres depth creates swim-throughs, overhangs, and channels where currents concentrate fish. Expect trevally schools, Napoleon wrasse, and frequent leopard shark sightings on the sandy bottom at 18–25 m. Suitable for Open Water divers.

East of Eden (Ko Payan) - A submerged pinnacle covered in soft coral that slopes from 12 to 35 metres. Experienced Advanced divers find this site consistently rewarding - the hard coral coverage is among the best remaining in the Andaman.

Beacon Reef (Ko Ha) - Gentler site with excellent visibility and reliable sightings of blue-spotted stingrays, pufferfish, and reef sharks cruising the sand channels.

A two-dive day trip for certified divers costs approximately THB 4,000–5,500 as of 2026, including tanks, weights, and a divemaster. Your own BCD and regulator saves roughly THB 300–500 in rental fees.

Introductory scuba (“try dives”)

Most operators offer a supervised introductory dive for non-certified guests at a shallow site (5–8 m). A divemaster accompanies you into the water, handles buoyancy, and keeps the dive short (20–30 minutes). Cost adds approximately THB 1,200–1,800 to the base snorkeling trip price. The experience is genuine - the Similan reef is impressive even at 5 metres - but if you think you might get certified later, it’s worth doing a full open-water course first to access the better sites on your own.

Liveaboards

Day trips suit most visitors, but if you want 3–4 days of diving with multiple sites per day, liveaboards are the serious option. Vessels like the MV Pawara and MV Whaleshark operate multi-night itineraries from Khao Lak, typically covering the Similans plus the Surin Islands and/or Richelieu Rock - one of the world’s best whale shark sites. Expect to pay THB 25,000–45,000 per person for a 3-night liveaboard, depending on the vessel and season.

When to go

The park is open approximately late October to mid-May. January to April gives the best visibility (often 25–30 m) and calmest seas. November and December are transitionally good - some swell but manageable. May is unpredictable as the season closes. Avoid going in the final two weeks of the season when conditions deteriorate and some operators have already stopped running.

Practical notes

• Book in advance in January–March: boats sell out 2–3 days ahead during peak season
• Sea sickness: The open-water crossing can be rough, especially in November–December. Carry motion sickness tablets if you’re susceptible
• Underwater cameras: Visibility is good enough to make a GoPro or waterproof camera worthwhile
• Rash vests: Bring your own or rent one (approximately THB 100–200/day); the sun reflects off the water and the coral can be sharp if you drift close

Cancellations do open up spots even in January peak season - our last-minute tours page is the fastest way to check what’s available tomorrow.

See also: Similan Islands guide · Things to do in Khao Lak area · Thailand island-hopping itinerary