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Over 20 Years of Experience Operating Tours to Exceed Your Expectations

Avoiding the Crowds with Personal

& Friendly Service

Highly Recommended by The Lonely Planet & The Koh Samui Guide
100% committed to the delivery of quality assured marine tours and personal service with attention to detail. 100 Degrees East is a family owned company with a friendly and knowledgeable team which endeavors to exceed your expectations, providing marine tour experiences that will be a memorable highlight of your holiday.
Our tours encompass all the top destinations in the Gulf of Thailand – Angthong National Marine Park, Koh Tao and Koh Phangan. Whether your interests lie above or below our beautiful tropical waters 100 Degrees East will take you there in safety and comfort.

On our tours we always guarantee our maximum number of guests on any tour to be only 12 adults, or 14 guests if we have children aged between 4 and 12 years. We always attempt to avoid other tour boats as much as possible and will alter our tour itinerary to make your day with us the best day of your holiday and a truly magical experience.

100 Degrees East is proud to be Koh Samui’s first plastic free marine tour operator. This small change means we no longer use thousands of plastic bottles every year. On our tours we offer reusable stainless steel water bottles for use which are also available to purchase at our center.
The 100 Degrees East tour to Angthong National Marine Park has been awarded the Tripadvisor Travelers’ Choice Best of the Best 2023 Award. Our tour is ranked 7th in the best of the best top experiences in the whole of Thailand.
Tripadvisor’s Travelers’ Choice awards represent the top 1% of businesses based on reviews and ratings from millions of travelers across the globe. Each winner has passed Tripadvisor’s rigorous trust and safety standards,signifying the highest level of excellence in travel. Join us to experience our tours for yourself!
Martyn J
What a magical day, perfection in paradise
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Credit where credit is due. Cara and her team know their stuff and deliver exceptional guided tours of Koh Samui and the surrounding area. From the inital contact to the final farewell the team make you feel like you are part of the family. We saw so many over crowded boats trips, ours was a perfect small group that worked so well.
Johanna W
You should not miss this trip!!!
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Wonderful daytrip perfectly organized by Cara and her amazing team. My husband went diving for the first time ever and our guide Ben was doing an amazing job to guide him through. We had a fantastic lunch at a beautiful bay, perfectly timed to avoid too many other divers. Second dive was great, as well. I loved every second of this trip, the rental equipment is in great shape, the boat is lovely, the entire crew is a joy to be with. Thank you so so much for this wonderful experience! Johanna & Helge
Kai D
Best thing to do in Samui
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Our experience with 100 degrees East was nothing short of incredible. The dive guide Ben was so knowledgeable about every aspect of the marine park, and the other boat staff were also very accommodating. Every aspect of the tour of the marine park was amazing! A+++ service
Greg D
Amazing Day Trip
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This was with out a doubt one of the best days I've had out in a long time. Roon and Cara have put together a special team. Big shout out to Chai for his patience and understanding (our young man has special needs) also what a photographer. Highly recommend 100 Degrees East.
100% recommend
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Team are very experienced whether you are a diver or a snorkeler. They know the best places for the best experience and clearest water, and just ensure you have a great experience, and go out of their way to make the trip extra special. Thanks 100 degrees east!
Brennan H
100 Degrees East is the best!
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We did the Angthong Marine Park tour, and it has been my favorite thing to see on Koh Samui. The tour is for smaller groups, so it is much more intimate and provides a better experience. We literally witnessed a couple get left behind on one of the islands from a separate tour so I definitely recommend going with these guys. Ben and Cara, you guys rock!
Exclusive Tours to Angthong National Marine Park & Koh Tao
Maximum 12 adults per tour
Luxury Holiday Diving for Both Certified & Introductory Divers
Limited Divers Per Tour
Speedboat Charters Tailored to Your Wishes to Stunning Destinations
Bespoke Services Just For You
'll Take You There