Diving on Koh Tao: Your Full 2025 Guide + Tips

Koh Tao has a reputation. Some say it’s just for cheap certifications. Others call it the best diving in Thailand.

I’ve spent more time diving here than anywhere else in the country, working as an instructor, logging countless fun dives, and getting to know these sites inside out.

So, is Koh Tao good for diving?

Absolutely. It’s one of the best places in the world to learn scuba diving, with warm water, calm conditions, and tons of dive sites that are perfect for beginners and fun divers. And if you’re already certified, there’s still plenty to explore beyond the basics.

But let’s keep it real, this isn’t Bali, Komodo or Raja Ampat. You’re not going to find insane currents, mind-blowing biodiversity, or remote frontier diving. What you will find is solid diving, easy logistics, affordable prices, and an island that’s built around the dive scene.

If you’re diving in Thailand, Koh Tao is an easy pick, especially if you’re just starting out or looking for relaxed, affordable dives.

This Koh Tao diving guide is packed with everything you need to plan your trip – dive sites, conditions, course prices, gear, safety tips, and my own recommendations from hundreds of dives here.

01 – Quick Guide to Diving Koh Tao

Category	Details
Best Time to Dive	March–April, September–October (best viz & calm seas)
Difficulty Level	Beginner-friendly
Top Marine Life	Whale sharks, barracuda, sting rays
Best Dive Sites	Chumphon Pinnacle, South West, Sail Rock
Diving Conditions	Viz: 10–30m, Currents: none to mild
Nearest Airport	Koh Samui (USM), then ferry to Koh Tao

Why Koh Tao Is Great for Diving

Scuba diving on Koh Tao is as easy as it gets: warm water, short boat rides, and dive sites for every level.

• 25+ dive sites close to shore – No long boat rides, just quick trips to great sites.
• Calm, warm conditions most of the year – Easy diving, especially for beginners.
• Beginner-friendly without being boring – Train on shallow reefs like White Rock and Twins, then level up to Chumphon Pinnacle or South West.
• Low prices for courses and fun dives – One of the most affordable places to dive.
• Small groups if you choose the right center – Avoid the cattle boats.
• Diving-focused island – Everything revolves around the water here, which makes planning simple.
• Plenty of competition – With so many dive centers, quality stays high, if you know how to choose the right one (more on that later).

Whether you’re learning to dive or logging your 100th dive, Koh Tao makes it easy to dive a lot and see a lot, without spending a fortune.

02 – Best Dive Sites on Koh Tao

There are over 25 dive sites around Koh Tao, but not all of them are worth your time. Here are my picks for the best dive sites around Koh Tao – these are the sites I keep diving again and again, no matter if I’m teaching or fun diving.

Chumphon Pinnacle

• Type: Pinnacle
• Depth: 14–35m
• Best For: Advanced divers, deep dives, big fish
• Marine Life: Barracuda, batfish, trevally, whale sharks
• Conditions: Can be rough at surface, prone to thermoclines

Chumphon is the best site around Koh Tao when conditions are good. And when it’s on, it’s incredible. This is where the big stuff happens.

You’ll see trevally and queenfish tearing through baitballs, barracuda stacking up in the blue, and batfish drifting through the thermocline. Whale sharks show up here too, especially around March–May and again in September.

Pro Tip: Go early in the morning when the visibility is best.

South West Pinnacle

• Type: Pinnacle
• Depth: 6–30m
• Best For: Intermediate to advanced divers
• Marine Life: Anemonefish, grouper, trevally, occasional whale sharks
• Conditions: Variable visibility, can get choppy

South West is another deep pinnacle covered in soft corals and sea anemones. It’s not as famous as Chumphon, but when conditions aren’t excellent out there, South West often pulls ahead.

There’s more reef fish action and fewer boats on the moorings. Look for shrimp, nudis, and tiny crabs hiding in the cracks of the granite pinnacle.

Pro Tip: Take your time along the west side of the main pinnacle. That’s where I’ve had the best macro finds between pelagic sightings.

Sail Rock

• Type: Pinnacle
• Depth: 5–40m
• Best For: All levels (with supervision)
• Marine Life: Huge schools of fish, barracuda, whalesharks
• Conditions: Open ocean, possible currents

This one’s not technically in Koh Tao but reachable via day trip. The chimney swim-through is the highlight, but the real draw is the schooling action and vertical walls full of marine life.

Sail Rock is a great spot to see whale sharks too. There can be some current, but it’s manageable.

Pro Tip: Only go with dive centers that use big boats, smaller ones can get rough in the open sea and it’s a long trip.

White Rock

• Type: Reef
• Depth: 5–22m
• Best For: Beginners, night dives
• Marine Life: Blue-spotted rays, moray eels, bannerfish, filefish
• Conditions: Easy, good visibility, very little current

White Rock is perfect for training dives and relaxed fun dives. It’s big enough to do two dives without seeing the same parts twice and shallow enough for good bottom time. The sandy patches in between coral heads make it a great place to spot stingrays.

Pro Tip: Dive it at sunset or do a night dive – it’s a completely different dive site, and you’ll have good chances to see octopus.

Shark Island

• Type: Rock island reef
• Depth: 5–25m
• Best For: Intermediate divers
• Marine Life: Soft corals, fusiliers, triggerfish, occasional reef sharks
• Conditions: Exposed to current and waves

Named after its shark fin shape (not because it’s full of sharks), Shark Island has some of the best coral coverage near Koh Tao. The south side has stunning soft corals and schools of fusiliers racing through the blue. It’s not the most sheltered site, so conditions vary more than the others.

Pro Tip: Dive the southern side for the best coral and fish life, just check the current beforehand.

Want a deeper dive into the island’s top sites? Here’s my full breakdown of the best dive sites on Koh Tao with more marine life highlights and tips.

03 – What You’ll See Underwater

You’ll hear a lot about Koh Tao being good for beginners, but that doesn’t mean the diving is boring. If you know where to go, there’s a solid mix of big stuff, macro life, and healthy reefs to explore.

Big Fish & Pelagics

Let’s be honest – everyone wants a whale shark. And yes, I’ve seen many here on Koh Tao.

They tend to show up around March to May and again September to October, usually at Chumphon Pinnacle, South West, or Sail Rock. But it’s always about being at the right spot at the right time.

Even without them, I’ve had dives where the trevally were going full-on feeding frenzy, darting into bait balls while giant groupers hid at the bottom. This kind of pelagic action is what makes Chumphon and South West worth diving, especially when the viz opens up.

Macro Life

Most people don’t come to Koh Tao for macro, but I do.

If you take your time and stick close to the reef, there’s plenty to find: nudibranchs, all sorts of shrimp, crabs, and the occasional ghost pipefish. You’ll find the best stuff in the cracks and ledges at sites like South West Pinnacle, Green Rock and White Rock.

I’ve had dives where students were distracted by the schools of snapper above us while I was losing my mind over a perfectly camouflaged nudi below them.

Coral Reefs & Artificial Sites

Not every reef around Koh Tao is in great shape, especially after the major bleaching event in 2024. But most spots are still worth diving. I really like Ao Leuk and Aow Mao, they have some of the most beautiful coral coverage.

Koh Tao also has a bunch of artificial reef sites that offer something a bit different. Places like Chalok Artificial Reef and Pottery are easy to access and great for macro life and juvenile fish.

And recently, two new wrecks have been added: the HTMS Suphairin 313 and HTMS Hanhak Sattru 312. They’re still new, but already starting to attract marine life and make for a nice change of pace from the usual reef dives.

Night Dives on Koh Tao

White Rock and Pottery are my go-to sites for night dives. Once the sun sets, they turn into completely different dive sites.

You’ll see blue-spotted stingrays moving over the sand, octopus hunting around the coral blocks, puffer fish looking for shelter, barracudas following your torch beam, and shrimps and crabs out in the open.

Honestly, some of my best dives in Koh Tao have been at night.

04 – Diving Conditions & Best Time to Dive

If you want the short version: March-April and September-October is generally the best time to dive on Koh Tao. You’ll get the best mix of visibility, calm seas, and whale shark sightings.

That said, I’ve dived here year-round, including in the worst of the monsoon, and while it’s doable, there are definitely better times to plan your trip.

Month	Visibility	Conditions	Notes
Jan–Feb	Improving	Can be wavy	Quieter season, hit or miss
Mar–May	Good	Some wind/swell	Whale shark season starts
Jun–Aug	Good	Warm water, light chop	Usually great diving
Sep–Oct	Excellent	Calm seas	Whale sharks around again
Nov–Dec	Poor	Unpredictable	Monsoon hits, not ideal for diving

Best Time to Dive Koh Tao

My favorite months are September and October.

September has that sweet spot where conditions are good, the water’s warm, and whale shark encounters start popping up.

October often brings glass-flat seas and 40+ meter viz – the kind of conditions that remind you why you love diving so much.

Rainy season (November – January) is a gamble. I’ve had a few nice dives in that window, but I’ve also had weeks where boats didn’t go out at all or viz was down to soup.

If you’re planning to take a course or do fun dives, avoid the monsoon unless you’re really flexible or really don’t care about visibility.

I break down what to expect each month – viz, temperature, whale sharks, the works – in my full guide to the best time to dive Koh Tao.

05 – Dive Courses, Fun Dives & Tec Diving

Whether you’re here to get certified, log more fun dives, or take things deeper with tec training, Koh Tao makes it easy. Prices are low, dive sites are close, and the conditions are perfect for learning or just enjoying the water.

I’ve taught courses here, fun dived with many dive centers, and seen both the good and the bad. Here’s what you can expect when it comes to training, dive trips, and tec diving on the island.

Dive Courses on Koh Tao

If you’re thinking about getting certified, Koh Tao is one of the best places in the world to do it. The course structure is the same everywhere, but the island’s warm water, easy conditions, and shallow reef sites make it a relaxed and low-stress environment to learn in.

Prices are some of the lowest you’ll find anywhere, but that doesn’t mean quality has to suffer – if you choose the right dive center. I’ll talk more about how to do that later.

Dive Course Prices on Koh Tao

Course	Duration	Approx. Price (THB)	Best For
Open Water	3–4 days	10,000–12,000	First-time divers
Advanced	2 days	8,000–10,000	Certified divers
Rescue Diver	3–4 days	12,000–14,000	Confident divers
Refresher	Half day	1,500–2,000	If it’s been a while since your last dive

Most courses include gear rental, instructor fees, boat trips, and certification. Some centers will also throw in accommodation, but that’s not always the best deal – check the room quality before committing.

Fun Diving on Koh Tao

Once you’re certified, Koh Tao makes it easy to dive a lot. Sites are close, conditions are chill, and boats run twice a day.

Most dive centers offer two-tank boat trips, usually leaving around 7:30 AM and around 12:30 PM. You’re back a few hours later, either in time for breakfast or with plenty of time before sunset drinks.

Fun Diving Prices on Koh Tao

• Two dives (local sites): 1,800–2,000 THB (€48–53 / $52–58)
• Two dives at Sail Rock: ~2,800 THB (€74 / $80)
• Night dive (one tank): ~1,200 THB (€32 / $34)

That usually includes full gear, dive guide, tanks, and boat – not insurance!

Discounts for packages: Most dive centers offer better rates if you book 6+ dives, worth asking about if you’re planning to dive for multiple days.

If you’re staying a bit longer, do a night dive. My favorite are Pottery and White Rock, there’s way more life after dark: blue-spotted rays, cuttlefish, parrotfish sleeping in their slime cocoons, and the occasional barracuda hunting through your torch beam.

Tec Diving on Koh Tao

Koh Tao might be known for Open Water courses, but there’s a solid tec diving scene here too – especially if you want to get into deco procedures, sidemount, or wreck diving without blowing your budget.

Tec Course Prices on Koh Tao

• Sidemount: 15,000–18,000 THB (€395–475 / $410–490)
• Tec 40 / Tec 50: 15,000–20,000 THB (€395–530 / $410–545)
• Advanced Wreck: 15,000–18,000 THB (€395–475 / $410–490)

You’ll find Tec setups with backmount doubles or sidemount rigs. Most dives are done from the usual boats, but you’ll usually have a separate setup area and schedule.

Depths around Koh Tao aren’t extreme, but they’re great for skill-focused training in deco, trim, and gas management.

I’ve trained with and seen good setups at Koh Tao Divers and Big Blue Tec. If you’re looking for tec training, make sure the center actually specializes in it. Not every dive center that offers tec courses really teaches them well.

06 – Dive Gear: Rent or Bring Your Own?

Most dive centers on Koh Tao offer decent rental gear and gear rental is usually included in course and fun diving prices, but the quality varies.

If you’re only diving for a couple of days, rental works fine. If you’re here to dive a lot, or you’re like me and you’re picky about your setup, it might be worth bringing your own.

I usually dive with my own gear, but I’ve seen plenty of rental gear while teaching on Koh Tao – everything from nearly-new gear to stuff that’s held together with zip ties.

What to Know About Rental Gear

• Regulators – Basic yoke regs are standard. Most breathe fine, but always do a proper check before the dive.
• BCDs – Standard jacket-style BCDs. Some are newer, others are well-worn, check for working inflators and valves.
• Wetsuits – 3mm shorties are the norm. The water’s warm, but I wear a full suit.
• Fins & Masks – Basic and functional. If you’re used to your own, bring them.
• Dive Computers – Not always included. If they’re not bundled, expect to pay 250–400 THB (€8–11 / $9–12) extra per day.

My Dive Setup for Koh Tao

Gear	What I Use	Why
Wetsuit	3mm full suit	I always freeze, even in warm water
BCD	Backplate and wing	More streamlined, better trim
Regulator	DIN reg with yoke adapter	Tanks are yoke, but I dive DIN
Fins	Lightweight tec fins	No current, no need for powerful fins

Not sure what to bring for your dives? Check out my Koh Tao packing list — it covers gear, essentials, and what you can leave behind.

07 – Best Dive Centers on Koh Tao

Choosing the right dive center on Koh Tao can feel like a challenge with so many options, but don’t worry, it doesn’t have to be complicated.

What to Look For in a Dive Center

• Group Sizes: Small groups are key. If you’re diving with more than 4 people, you’re probably not getting the attention or experience you deserve. Smaller groups mean more time with the instructor, less waiting around, and a better dive overall.
• Gear Quality: The gear doesn’t have to be shiny-new, but it should be well-maintained. I’ve seen gear that’s seen better days, and trust me, you don’t want to be diving with equipment you don’t trust. Always check your gear before heading out.
• Instructor Experience: It’s not just about knowing the dive sites, it’s about making you feel comfortable. The best instructors are calm, patient, and make sure you’re safe and confident in the water. If you’re taking a course, look for reviews that talk about the quality of the teaching and the instructor’s experience.
• Safety: Don’t just assume safety is covered – ask about it. Good dive centers will have clear safety procedures and be able to tell you where the nearest chamber is (just in case). If a dive center is hesitant to talk about safety, that’s a red flag.

My Personal Picks

I’ve worked and dived with a lot of centers here, and these are the ones I’d send my friends to:

Hydronauts – They offer a chill yet professional vibe, keep groups small, and make sure you feel comfortable. If you’re looking for courses, the instructors make learning relaxed and straightforward without overcomplicating things.

Koh Tao Divers – This one’s a bit of a Koh Tao staple, but for good reason. They’ve got a great crew, a relaxed atmosphere, and their dive operations are smooth. Needless to say, Koh Tao Divers is one of the best dive centers on the island for technical courses.

A Note on Party Dive Centers – Koh Tao has a party scene, but diving and hangovers don’t mix. Avoid centers that push the party vibe. The best dive centers focus on safety and quality diving, with socializing as a nice bonus, not the main event.

08 – Dive Safety On Koh Tao

Working in a hyperbaric chamber has shown me how fast accidents can happen. That’s why I never dive without knowing where the nearest chamber is and making sure my insurance covers the kind of diving I’ll be doing. It’s a simple step that makes a huge difference when it comes to peace of mind on a trip.

Have Dive Insurance

Most dive centers on Koh Tao include insurance for courses only (often not higher than open water) and don’t cover fun diving. Make sure you ask when booking your dives.

Proper dive insurance is non-negotiable. You want coverage for repetitive dives, chamber treatment, and evacuation if needed.

I’ve treated plenty of divers, from beginners to tec instructors, and can recommend these three insurance providers – they have consistently come through for patients:

• DAN (Divers Alert Network) – My personal choice
• Dive Assure
• Dive Assist

Hyperbaric Chamber

Koh Tao has a dedicated hyperbaric chamber for treating divers. It’s fully equipped, staffed, and operational.

But just because it’s there doesn’t mean you want to use it. During high season, cases go up often because people dive dehydrated or overestimate their limits.

Common Dive Risks on Koh Tao

• Watch the group size – Some dive centers keep things tight and professional. Others will throw 8 fun divers behind one guide and hope for the best. Make sure you get the attention you deserve and ask for group size before booking.
• Dehydration – The sun, heat, and daily diving add up. Drink more water than you think you need. During high season, DCS cases go up because people dive dehydrated without realising. Skip the crazy parties until your last dive is logged.
• Remote Location – Koh Tao has a hyperbaric chamber, but its hospital is far from western standards. The next medical facilities are on Koh Samui, so dive conservatively and be careful on the boat and the streets.

09 – Marine Conservation & Responsible Diving

Koh Tao sees a huge number of divers every year, and while that’s great for the local economy, it puts pressure on the reefs. The good news? There’s a strong conservation community here, and it’s easy to dive in a way that doesn’t wreck the place.

• Support Local Conservation Projects – Several dive centers on Koh Tao are involved in reef restoration and clean-up dives. One I recommend checking out is Global Reef—they run hands-on marine conservation internships and research programs that focus on protecting coral reefs and marine ecosystems.
• Buoyancy Is Everything – Want to protect the reef? Nail your buoyancy. I’ve seen more damage from poor trim and flailing fins than from anything else. If you’re not confident, take a buoyancy class or just take the time to slow down and stay controlled.
• Don’t Touch Anything – Seriously. No matter how cool it looks. Coral takes years to grow, and even a light touch can do real damage. Same goes for picking up shells or trying to move marine life for a better photo.
• Use Reef-Safe Sunscreen – A lot of common sunscreens contain chemicals that harm coral. Go for mineral-based, reef-safe products—or better yet, wear a rash guard and skip sunscreen on dive days altogether.
• Choose Ethical Dive Centers – Not every center operates with the reef’s best interest in mind. Look for places that:
  • Limit group sizes
  • Avoid anchoring (they should use mooring lines)
  • Participate in reef clean-ups or conservation
  • Actually enforce no-touch, no-chase diving policies

The reef doesn’t owe us anything. If you want it to still be there next time you come back, dive in a way that helps protect it.

10 – Tips for Diving on Koh Tao

A few things I’ve learned from diving here over and over again:

• Don’t chase dive sites, chase conditions – Everyone wants Chumphon, but I’ve had better dives at Green Rock in average viz than Chumphon in a current.
• Avoid peak season – July–August and holidays get packed. Come in May–June or September–October for fewer crowds
• Bring snacks and hydrate – Most boats have water and fruit, but long dive days in the heat will drain you. I always bring my own water bottle and a few salty snacks, especially if I’m doing back-to-back dives.
• Ask questions before you book – Group size, guide experience, and boat setup all vary. A good dive center will happily talk you through how they run things. If they seem annoyed or vague, go somewhere else.
• Leave time before flying – Standard advice, but worth repeating. If you’re doing a lot of diving, give yourself at least 24 hours after your last dive before flying out.

11 – Getting to Koh Tao

Getting to Koh Tao isn’t complicated, but it does take a bit of planning. Here’s how I usually do it, and how you can too.

Fly to Koh Samui + Ferry

The most straightforward way is to fly from Bangkok to Koh Samui. From there, it’s a quick ferry ride to Koh Tao, about 2 hours. You can easily book a ferry + transfer combo at the airport when you land, or book online in advance. It’s a smooth, simple option but not cheap.

Train from Bangkok & Ferry

If you’re after a more budget-friendly option, you can take a train from Bangkok to Chumphon and then catch the ferry. It’s a longer trip, but if you’ve got the time and enjoy the journey, it’s a good choice. The train ride is an overnight experience, and the ferry ride takes about 1.5 hours.

Bus from Bangkok & Ferry

The bus and ferry combo is another popular choice. Buses from Bangkok or Chumphon head to the ferry terminal, and from there it’s a 1.5-hour boat ride to Koh Tao. It’s another low-cost option, but do check schedules ahead of time.

For all the nitty-gritty details on getting to Koh Tao, including transport options and tips, I’ve put together a step-by-step guide from Bangkok to Koh Tao.

Whenever I travel to or from Koh Tao, I book tickets through 12Go Asia. It’s the easiest way to compare routes, check ferry times, and book your train, bus, or flight in one go. Highly recommend it if you want to avoid last-minute surprises.

12 – Best Place to Stay on Koh Tao

Koh Tao has three main areas where most divers base themselves: Sairee, Mae Haad, and Chalok.

I’ve stayed in all of them, and each one has a different vibe depending on what kind of dive trip you’re after.

• Sairee – The busiest part of the island. It’s full of hostels, beach bars, and party crowds. If you’re here to do serious diving, I wouldn’t stay in Sairee. It gets loud, and the party scene can get in the way of early mornings and dives. That said, a few good dive centers are based on the quieter ends of the beach, so it’s not off-limits, just choose carefully.
• Mae Haad – Right by the ferry pier and much calmer than Sairee. You’ve got a few good dive centers here, a handful of restaurants and shops, and no massive nightlife, which makes it great if you’re here to dive and chill. I currently live in Mae Haad, it’s convenient and chill.
• Chalok – Quieter, with more of a local vibe. There are fewer people, less development, and a much slower pace. It’s ideal if you want to stay somewhere peaceful and just focus on diving.

Once you’ve picked the vibe that suits you, here’s the real tip: Choose your dive center first, then book accommodation nearby.

Koh Tao’s not huge, but staying close to your dive center makes life a lot easier, especially if you’re carrying your own gear or doing multiple dives a day. Most dive centers can also help you sort out accommodation or make recommendations, which is worth asking about.

I’ve also put together a breakdown of the best places to stay on the island including hotel recommendations based on diving, location, and budget to help make your choice easier.

13 – Best Non-Diving Activities

Even if you’re here to dive, there’s plenty to do on the surface, no matter if it’s for a chill afternoon between dives or something to keep your travel buddy entertained while you’re underwater.

• Snorkeling – Koh Tao has some excellent snorkel spots, especially at Shark Bay, Ao Leuk, and Tanote Bay. You can rent snorkeling gear pretty much anywhere, or join a half-day snorkel tour that hits the main bays.
• Hiking & Viewpoints – If you’re up for a bit of a climb, the island has some really good views. John-Suwan Viewpoint and Fraggle Rock are two of my favorites, short hikes with a big payoff.
• Beaches – Between dives, you’ve got plenty of options to just relax. Sai Daeng is great for a quiet beach day, and Tanote Bay is perfect if you want to snorkel straight off the sand.
• Cafés & Food – Koh Tao has many great places to grab a smoothie bowl or Thai Curry. Mae Haad, Sairee, and Chalok are full of options, from local Thai restaurants to places serving western food like pizza and burgers.

If you’re sticking around after your dive days or want to fill in some time between dives, I put together a full list of surface interval-friendly things to do all over the island.

FAQ: Diving on Koh Tao

Before You Go

If you’re planning a dive trip to Thailand, Koh Tao is a great place to start. It’s affordable, easy to dive, and full of good sites.

Getting to Koh Tao is part of the adventure, especially if you’re coming from Bangkok. I’ve broken down the best ways to reach the island step by step so you know what to expect.

Bring a mask too, some of the best snorkeling spots on the island are easy to reach from shore and can honestly be better than the shallow dive sites.

And if you’ve got a non-diving travel buddy or just need a dry day, there’s plenty to do above the surface. From hiking trails and hidden beaches to chilled-out viewpoints, I’ve put together a full list of things to do on Koh Tao that’ll keep your surface intervals interesting.

Still have questions about diving on Koh Tao? Feel free to reach out – drop a comment below or get in touch via email. If you find this guide helpful, feel free to share it with your dive buddies. They might just end up joining you on the next dive.