Koh Samui Sailing Guide for Yachts

Koh Samui Sailing Guide for Yachts. Koh Samui is the primary yacht base in the Gulf of Thailand, used for provisioning, fuel, water, and crew movements when operating between Koh Phangan, Koh Tao, Pattaya, and the Surat Thani mainland ports. The island sits on a broad shallow shelf, with depths reducing from 20–25 m offshore to 6–10 m near the coast. Navigation is shaped by reefs, coral heads, ferry routes, and seasonal swell, and anchorages shift with the monsoon cycle.

Services are concentrated around Bophut, Maenam, Chaweng, and Lamai. Markets operate daily, seafood supply reflects local landings, and supermarkets maintain predictable stock levels. The north coast provides the most consistent anchoring during the northeast monsoon, while the east coast is used in calmer periods.

Koh Samui Sailing Guide for Yachts - Approaches

Approaching Koh Samui is generally straightforward, though the island is surrounded by shallow shelves and sand patches that require attention. Navionics and C‑Map provide reliable coverage. Depths decrease gradually when approaching from the east or north, and yachts should maintain a safe offing until identifying the anchorage.  Numerous fishing boats operate close to shore, few have AIS. Fixed fishing traps and floating lines are common, especially west of the island. Unlit buoys and small craft make night arrivals possible but not ideal.  Swell wraps into exposed bays during strong winds.  Bo Phut Bay offers the easiest approach with clear depths. Chaweng and Lamai have shallow shelves; approach slowly and visually. Nathon is deep but busy with ferries; anchoring is possible outside the main channel.

Depths reduce from 20–25 m offshore to 10–12 m, then 6–10 m inside the shelf. Fringing reefs extend offshore on the east and southeast coasts, with coral heads rising into 4–6 m near Chaweng and Lamai. The north coast has isolated coral patches in 5–8 m and sandbars that shift after storms. Ferry traffic between Samui, Phangan, and the mainland is continuous, with high‑speed catamarans crossing yacht tracks at speed. Seasonal mooring fields extend into 8–10 m in Bophut and Chaweng. The northeast monsoon produces short, steep seas on the east coast. Tidal range is moderate, and currents are generally weak.

Koh Samui Sailing Guide for Yachts - Anchorage

Most anchorages are on sand with good holding. Coral areas are marked by buoys and should be avoided. Tidal range is modest, but strong onshore winds can create uncomfortable conditions in open bays. Bophut and Maenam provide the most reliable anchoring in 6–12 m over sand. The east coast becomes exposed during the northeast monsoon, with Chaweng and Lamai often untenable due to onshore swell and shallow bars in 3–5 m. The Five Islands offer 8–14 m in settled weather, with coral shelves rising into 4–6 m. Holding varies from firm sand to mixed sand and rubble. Anchorage selection must avoid ferry lanes and seasonal mooring fields.

Bophut Beach provides the most consistent dinghy access, with 0.5–1.5 m of water at the shoreline depending on tide and swell. Maenam Beach offers similar conditions but with more long‑tail traffic. Chaweng Beach is often unusable during the northeast monsoon due to surf and onshore swell. Good for short stays. Dinghies must be secured above the high‑water line due to shifting beach gradients and local boat movements. Bo Phut Bay. One of the most reliable anchorages with good holding and dinghy access to Fisherman’s Village. Lamai Bay is an open anchorage with workable holding; best in calm conditions. Nathon Pier is the main commercial port. Dinghy access possible but busy with ferries. Bang Rak is a sheltered anchorage near the airport.

Koh Samui Sailing Guide for Yachts - Entry Formalities

Koh Samui is an official port of entry for Thailand, though procedures are simpler when handled through the main offices in Nathon. Required Documents are Vessel registration, Passports, Crew list, Insurance, Last port clearance (if arriving internationally). Domestic movements between Samui, Phangan, and Tao require no further clearance once entry is completed. Harbour inspections occur as required. Starlink and other satellite systems are permitted but must not interfere with local frequencies.

Process is anchor off Nathon or Bo Phut. Dinghy ashore to Nathon Pier. Complete Immigration, Customs, and Marine Department paperwork. Receive a temporary import permit for the vessel (valid up to six months). Most nationalities receive a 30‑day visa on arrival, with extensions available at immigration offices. Yachts moving between Koh Samui and other Thai ports must file a domestic movement report, usually handled online or at the Marine Department. Agents are not required but can simplify the process, especially for vessels with multiple crew changes.

Koh Samui Sailing Guide for Yachts - Marina Facilities

Koh Samui has no full‑service marina and no dedicated yacht berths. All visiting yachts anchor off Bophut or Maenam and access shore by dinghy. There are no floating pontoons, no finger berths, no fuel dock, no pump‑out, and no haul‑out or hard‑stand anywhere on the island.

Resort piers at Bophut, Maenam, and Chaweng provide limited short‑stay access for tenders only. Depths at these piers range from 1–3 m at low water, with some sections drying at extreme tides. Most piers are built for long‑tail boats and small ferries, not yachts, and access is controlled by resort management. Swell affects all east‑coast piers during the northeast monsoon, making landings unreliable.

Koh Samui Sailing Guide for Yachts - Local Weather

Koh Samui’s weather differs from the Andaman coast and follows the Gulf of Thailand’s seasonal pattern. Koh Samui is outside the main cyclone belt, and severe storms are rare. Rainfall peaks from October to December.

• Northeast Monsoon (December–April). This is the dry season, with NE winds and relatively calm seas. Anchorages on the north and west coasts are most reliable. Visibility is good, and rainfall is low.
• Southwest Monsoon (May–October). The wet season brings SW winds, frequent squalls, and rougher seas on the west and south coasts. Bo Phut and Bang Rak remain workable, while Chaweng and Lamai become exposed.
• Transition Months (November and April). Conditions vary, with occasional storms and shifting winds. Transitional periods provide the most settled weather for inter‑island passages. Visibility is generally good, with occasional haze during regional burning periods

Koh Samui Sailing Guide for Yachts - Provisioning

Supermarkets. Supermarkets are located in Bophut and Chaweng. Lotus’s Bophut, Big C Chaweng, and Makro Chaweng carry vegetables, herbs, fruit, dairy, dry goods, and packaged imports. Deliveries from the mainland maintain stable stock levels. Makro provides the most reliable bulk quantities for longer passages. Specialty products, including bakery items and Western packaged goods, are available in Central Festival Chaweng, though availability varies seasonally.

Markets. Bophut Fresh Market and Lamai Market operate daily with high turnover. Both supply local greens, herbs, tropical fruit, tofu, noodles, and fresh curry pastes. Morning trading provides the widest selection. Produce arrives from Surat Thani and local farms, and availability remains stable year‑round.

Fish Markets.  Seafood reflects local Gulf landings. Bophut Market, Lamai Market, and roadside seafood stalls carry prawns, squid, coastal fish, and shellfish landed overnight and sold through the morning. Turnover is highest before midday, and availability varies with weather and fishing conditions. Quality is consistent due to rapid local consumption.

Koh Samui Sailing Guide for Yachts - Local Cuisine

Koh Samui’s cuisine reflects Gulf seafood and southern Thai preparation styles, with dishes built around squid, prawns, coastal fish, coconut, lemongrass, and fresh herbs. Steamed fish dishes such as pla kapong neung manao use whole sea bass with lime, garlic, and chilli, while mixed‑seafood salads like yum talay combine prawns, squid, and shellfish with herbs and lime dressing. Everyday dishes include pad krapao with chicken or pork, pad thai, khao man gai, and a range of kuay teow noodle soups prepared with pork broth or fish balls. Southern influences appear in coconut‑based curries such as gaeng som, gaeng khua, and massaman, with spice levels varying by vendor. Street stalls prepare khao pad, gai yang, and fast‑turnover seafood stir‑fries tied to local landings, with prawns, squid, and coastal fish moving quickly through evening markets and food courts.

Koh Samui Sailing Guide for Yachts - Fuel Supplies

Diesel is obtained by jerry can from roadside stations across the island. Supply is reliable, and stations operate long hours. Fuel delivery can be arranged through agents in Bophut and Maenam. Quality is generally consistent, though checks for water or sediment are recommended when purchasing from smaller outlets.

Koh Samui Sailing Guide for Yachts - Water Supplies

Potable water is supplied by local vendors in Bophut and Maenam, with delivery arranged through agents or resort contacts. Onboard filtration is standard practice. Outside main centres, water is collected by jerry can from municipal taps or roadside stations, with variable pressure and occasional sediment.

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Koh Samui Sailing Guide for Yachts - Marine Services

Marine services are limited. Mechanics, electricians, and general repair technicians operate through local agents. Fibreglass and small‑engine work can be arranged. Major engine work, including Volvo and Yanmar servicing, is handled on the mainland or in Phuket. Gas refills, laundry, SIM cards, and hardware supplies are available in Bophut and Chaweng.

Koh Samui Sailing Guide for Yachts - Local Customs

Koh Samui follows national norms shaped by Buddhism and strong reverence for the monarchy. Respectful behaviour is required near temples and religious sites. Lèse‑majesté laws apply. Public confrontation is discouraged. Alcohol sale hours are regulated. Waste disposal rules apply near beaches, resort zones, and marine‑protected areas. Politeness and calm behaviour are valued. Remove shoes before entering homes or temples. Dress modestly in government offices and religious sites. Public displays of anger are discouraged. English is widely spoken in tourist areas but less common in markets. Interactions with officials are generally straightforward, and patience is appreciated.

Koh Samui Sailing Guide for Yachts - Summary

Koh Samui provides reliable provisioning, fuel, water, and basic services for yachts operating in the Gulf of Thailand. Navigation requires attention to reefs, shallow shelves, ferry routes, and seasonal swell. Anchorages shift with the monsoon cycle, with the north coast offering the most consistent shelter. The island functions as a practical staging point for movements to Phangan, Tao, Pattaya, and the mainland. Koh Samui Sailing Guide for Yachts has all you need to know.