Snorkelling around Koh Samui can be a really lovely experience, especially if you know where to go and when to go. While snorkelling directly off Samui’s main beaches is fairly limited, the surrounding islands offer much better conditions, clearer water, and more abundant marine life.

With short boat journeys, calm seas for much of the year, and a mix of easy reef snorkelling and more adventurous spots, Koh Samui is a great base for exploring some of the best snorkelling in the Gulf of Thailand.

This guide will help you choose the best snorkelling spots near Koh Samui, understand what to expect at each location, and plan your trip for the best time of year.

Koh Taen (Coral Island)

Best for: Calm water, coral gardens, beginners
Best time to visit: February to September

Koh Taen (also known as Coral Island) is one of the most reliable and accessible snorkelling spots near Koh Samui. Located just 15 minutes by longtail boat from the mainland, it’s ideal if you want a relaxed snorkelling experience without a long journey.

The coral sits in shallow water, the sea is usually calm, and there’s plenty of colourful reef fish to spot without needing to swim far from the boat. This makes Koh Taen particularly suitable for families, first-time snorkellers, or anyone who prefers an easy and enjoyable experience.

Koh Taen works beautifully as a half-day or full-day trip, especially when combined with time to relax on the boat and enjoy the scenery.

Discover our private luxury longtail experiences, designed for relaxed island hopping and unhurried snorkelling.

Ang Thong National Marine Park

Best for: Scenic snorkelling and dramatic island views
Best time to visit: March to October

Ang Thong Marine Park is famous for its towering limestone islands, emerald-green lagoons and breathtaking scenery. On calm days, snorkelling here is a beautiful addition to the experience, with clear water and colourful marine life set against one of the most dramatic backdrops in Thailand.

Snorkelling is a wonderful addition to a day spent kayaking, visiting viewpoints and exploring the islands. With the right itinerary and timing, you can enjoy clear water and relaxed snorkelling alongside everything else Ang Thong has to offer.

For travellers who want to avoid large crowds and busy snorkelling stops, selecting a more considered itinerary is key.

Take a look at our Ang Thong collection to see the different ways you can experience this stunning marine park.

Koh Tao (For the Best Snorkelling)

Best for: The best marine life near Koh Samui
Best time to visit: March to September

If snorkelling is a top priority on your holiday, Koh Tao is the standout option. Widely regarded as one of the best places in Thailand for snorkelling and diving, Koh Tao offers healthier coral reefs, clearer water, and a much wider variety of marine life.

It’s common to see turtles and dense coral systems here, making it a favourite for travellers who want the strongest snorkelling experience in the region. The journey takes around 1.5 hours from Koh Samui, making it a longer day trip, but when conditions are right, the snorkelling is genuinely world-class.

Our Koh Tao collection offers a variety of ways to explore this famous island. 

Koh Phangan & Koh Ma

Best for: Casual snorkelling and easy access
Best time to visit: February to September

Koh Phangan and nearby Koh Ma offer snorkelling opportunities that are worth mentioning, especially if you’re already planning to visit the island. Koh Ma, connected to Koh Phangan by a sandbar, has shallow reefs that can be enjoyable on calm days.

While the coral here isn’t as impressive as Koh Tao, these spots can still be pleasant for light snorkelling, particularly for beginners or those looking for something easy and accessible.

When Is the Best Time to Snorkel Around Koh Samui?

February to September
This is the best season for snorkelling around Koh Samui and the surrounding islands. Seas are generally calmer, visibility is better, and conditions are more reliable for planning boat trips.

October to January
This is monsoon season in the Gulf of Thailand. Some days can still be suitable, but visibility is often reduced and snorkelling cannot be guaranteed.

A Few Helpful Snorkelling Tips

• Morning trips usually offer clearer water and calmer seas
• Smaller boats create a quieter, more relaxed snorkelling experience
• Weather conditions are just as important as location
• Snorkelling around Koh Samui is relaxed and enjoyable, rather than extreme reef diving

If you’re looking for easy, stress-free snorkelling, Koh Taen and Koh Mudsum are excellent choices. If you want the best reefs and marine life, Koh Tao is well worth the extra travel. And if you’re drawn to dramatic scenery with a snorkelling stop, Ang Thong Marine Park is a beautiful option.

Snorkelling around Koh Samui is all about choosing the right experience, and when you do, it’s a wonderful way to spend time on the sea.