But here’s what 25 years on this island have taught us : St Martin and Sint Maarten are small. No beach is ever more than 15 minutes from another. If one shore is affected by sargassum seaweed, a cleaner one is always within reach — and our map will show you exactly where to go.
We built this live sargassum and seaweed map for our readers and guests, so you can plan your beach day with confidence and spend less time worrying about algae and more time enjoying the Caribbean. Because sargassum is part of Nature — and Saint-Martin always has a beautiful alternative waiting for you.
🟢 Green: Clear conditions reported in the last 24 hours. Safe to swim.
🟠 Orange: Moderate seaweed presence. Swimmable but noticeable.
🔴 Red: Heavy sargassum. Expect thick seaweed on the shore.
Check the live map above for real-time conditions. Each beach is color-coded based on reports submitted in the last 24 hours by locals and visitors on the ground.
The eastern beaches — Orient Beach, Cul de Sac, Coralita and Oyster Pond — are the most exposed because they face the open Atlantic. When sargassum seaweed levels are high, the western and northern beaches such as Grand Case, Friar's Bay and Baie Rouge are usually the best alternatives.
Yes, sargassum is not dangerous. It is a natural seaweed that can be unpleasant to swim through but poses no health risk for most people. If you are sensitive to strong smells or have skin sensitivities, we recommend choosing a green-rated beach on the map.
Sargassum has been a regular feature of Caribbean beaches since 2011. On St Martin, the season typically begins in late March or early April, peaks between May and August, and tapers off by October. Outside of this window — from November through February — most beaches remain clear. That said, intensity varies significantly from year to year depending on ocean currents, wind patterns and Atlantic bloom conditions.
The map is updated in real time. Anyone on the beach can submit a condition report directly from the map — no account required. Reports expire after 24 hours so the information always stays current.
Simply check the map for the nearest green beach. On an island this small, a clear beach is never more than 15 minutes away. Grand Case, Friar's Bay and Anse Marcel are reliable alternatives on the French side. Mullet Bay and Simpson Bay tend to stay cleaner on the Dutch side.
Yes — and we encourage it. Click on any beach marker on the map and select the condition you observe. Your report helps other visitors plan their day. Reports are anonymous and take less than 10 seconds.
The beach is just the beginning. Whether the water is clear or the sargassum has other plans, St Martin always has something extraordinary waiting. Explore the best things to do on the island →
Looking for a beach day with a twist? A catamaran tour takes you to Tintamarre — one of the clearest, most pristine shores in the Caribbean. Or escape the island entirely with a day trip to Anguilla — 20 minutes away, consistently sargassum-free.
Need a car to explore the beaches? Rent a car in St Maarten →
Disclaimer : Beach conditions are reported by locals and visitors in real time. This map is for informational purposes only — conditions can change within hours.
BookStMartin.com provides this map as a community service and accepts no liability for decisions made based on reported conditions.
