Where is the Gulf of Thailand?
The Gulf of Thailand is the shallow sea on the east side of Thailand's long southern arm. Encyclopaedia Britannica describes it as an inlet of the South China Sea, 500 to 560 kilometres wide and about 725 kilometres long. Thailand lines its west and north shores, with Cambodia and southern Vietnam to the north-east.
Is it part of the Pacific Ocean? In a broad sense, yes. The South China Sea is a marginal sea of the western Pacific, and the Gulf opens into it. Thailand's other coast, on the west, faces the Andaman Sea, which belongs to the Indian Ocean.
It is July, Phuket is wet, and you want a beach. That is when the Gulf earns its place: calm, warm water, a coast close to Bangkok and a group of famous islands.
The water here is shallower and usually calmer than on the Andaman side. Beaches on the east-facing shores catch the sunrise, while the west coasts of the islands catch the sunset. Limestone cliffs are fewer than around Phuket and Krabi, but the bays are softer, greener and often quieter.
Gulf coast or Andaman coast: which suits your dates?
Choose the coast by the month you travel. The Andaman coast, with Phuket and Krabi, is driest from December to March. The Gulf, with Koh Samui, is driest from February to April and stays fairly good through the summer. The Gulf's wettest months are October to December, peaking in November.
The Thai Meteorological Department's records for Koh Samui show November is the wettest month, with about 445 millimetres of rain. February is the driest. January is still fairly wet, so the best stretch is February to April.
A simple month guide for the Gulf islands: January is mixed, with some rain. February, March and April are the best months. May to September are mostly good, with short showers. October brings more rain, November is the wettest, and December starts to improve.
Hua Hin on the mainland follows a similar pattern. The Thai Meteorological Department says the north-east monsoon raises high waves off this coast in the cool season. Our Phuket vs Koh Samui guide compares the two coasts in more detail.
Hua Hin, Cha-am, Khao Takiab and Pranburi: the royal coast
Hua Hin is the classic beach town of the Gulf, about 200 kilometres from Bangkok by road. Thai royalty has spent summers here for generations, and the town keeps a calm, refined feel. Cha-am lies just north, Khao Takiab just south, and Pranburi further south again, each quieter than Hua Hin itself.
Hua Hin. InterContinental Hua Hin lists Hua Hin Airport as ten minutes away. The town has large beach resorts, golf courses, night markets and a historic railway station. The InterContinental, Centara Grand, Hilton and Marriott all have beachfront hotels here, and Chiva-Som is one of Asia's best-known wellness resorts. See our Hua Hin guide.
Hua Hin works well as a long weekend from Bangkok, or as a calm last stop before a flight home. Golf is a big draw, with several courses in the hills behind town. Nature lovers can visit Khao Sam Roi Yot National Park to the south, where the Department of National Parks charges ฿200 per foreign adult.
Cha-am. A long, quiet beach popular with Thai families at weekends. Book it for space and a calm resort week. See our Cha-am guide.
Khao Takiab. A small hill with a temple and monkeys at the south end of Hua Hin beach. Hyatt Regency Hua Hin sits nearby. See our Khao Takiab guide.
Pranburi. Quiet beaches, pine trees and boutique resorts. Aleenta says Pranburi is about two and a half hours from Bangkok by car and thirty minutes beyond Hua Hin. See our Pranburi guide.
What is the quiet coast south of Hua Hin like?
South of Hua Hin, the Gulf coast becomes quieter and more local. Prachuap Khiri Khan town has a beautiful curved bay and limestone hills. Further south, Chumphon is the main gateway to Koh Tao by ferry. Come here for real Thai coastal life, not a resort strip.
Prachuap Khiri Khan. The province runs from Hua Hin down to the narrowest part of Thailand. Its town bay is calm, clean and lined with seafood restaurants. See our Prachuap Khiri Khan guide.
Chumphon. The State Railway of Thailand timetable shows Special Express 43 leaving Bangkok at 07:30 and reaching Chumphon at 13:50. From Chumphon's piers, ferries cross to Koh Tao. The coast has quiet beaches and good diving offshore. See our Chumphon guide.
The coast between them has long, empty beaches and small fishing towns. Neither town has a true luxury resort. We use them as stops on a slow road trip, or as the start of a sea crossing. We book the best available hotel for one night.
Koh Samui and its beaches
Koh Samui is the main luxury island of the Gulf, with an airport, outstanding resorts and a wide choice of beaches. Each beach has its own mood. Chaweng is lively, Lamai is relaxed, Bophut has charm and dining, and the north and west coasts are the quietest. The White Lotus season 3 was filmed at Four Seasons Resort Koh Samui.
Chaweng. The busiest beach, with the most restaurants and bars. Centara says it is about ten minutes from the airport. See our Chaweng guide.
Lamai. Softer and calmer than Chaweng, with rocky headlands. Banyan Tree Samui says it is about 19 kilometres and 30 minutes from the airport. See our Lamai guide.
Bophut. The old Fisherman's Village, good restaurants and resorts such as Six Senses Samui and Anantara Bophut. See our Bophut guide.
Choeng Mon. Small, sheltered bays in the north-east, close to the airport. Kimpton Kitalay and Cape Fahn are here. See our Choeng Mon guide.
Maenam. A long, quiet north-coast beach with views of Koh Phangan. See our Maenam guide.
Lipa Noi. The calm west coast, with shallow water and sunsets. See our Lipa Noi guide.
For the whole island, start with our Koh Samui guide.
How to choose a beach: for calm and privacy, book Choeng Mon or the north coast. For children, Bophut and Maenam have gentle water. For the most restaurants and bars close to your hotel, take Chaweng. For wellness, consider Absolute Sanctuary, which says it is five minutes from the airport.
For a group, a private pool villa with a chef beats a row of hotel rooms. Samui's largest villas have about 10 bedrooms for about 20 guests. We describe each villa by its bedrooms, beach and view, and show you real photos before you choose.
Koh Phangan and Koh Tao
Koh Phangan and Koh Tao lie north of Koh Samui. Koh Phangan is greener and quieter than its reputation, with remote bays and wellness retreats. Koh Tao is small and known for diving. Both are reached by boat from Koh Samui, and a private speedboat makes the crossing simple.
Koh Phangan. The island is best known for the Full Moon Party at Haad Rin. The 2027 dates start on 22 January, 22 February and 22 March. Away from Haad Rin, bays such as Thong Nai Pan are calm, with resorts such as Anantara Rasananda Koh Phangan Villas. Phangan International Hospital, a Bangkok Hospital Samui branch, operates on the island. See our Koh Phangan guide.
Koh Tao. A small island of granite boulders, clear bays and dive schools. It suits divers and snorkellers more than resort lovers. Many first-time divers learn here, and the calm bays on the east side are good for snorkelling with children. Hotels are smaller and simpler than on Koh Samui. Our advice is to visit for a day by private boat. See our Koh Tao guide.
Koh Phangan also has a royal history. The Tourism Authority of Thailand notes that King Rama V visited the island 14 times between 1888 and 1909. He carved his initials on stones near the waterfalls. Today the island is also known for yoga and wellness retreats in its quieter bays.
Island-hopping the Gulf by yacht
The best way to see the Gulf islands is on a private yacht from Koh Samui. You leave after breakfast, swim in a quiet lagoon by late morning and eat lunch at anchor. In one day you can reach Ang Thong Marine National Park, Koh Phangan's quiet bays or Koh Tao's reefs. Seaplanes are not licensed in Thailand today, so we do not plan around them.
Ang Thong is a marine park of steep green islands, hidden lagoons and viewpoints. The Department of National Parks closes it from 1 November to 15 December 2026. After that date, private boats can visit again, and the park charges a special-area fee of ฿300 per foreign adult.
A longer trip can link Koh Samui, Koh Phangan and Koh Tao over two or three days, with nights in calm bays. Our yacht charter in Koh Samui page explains boats, routes and how pricing works.
Choose your season with care. From October to December the sea can be rough, and some crossings are cancelled.
Getting to the Gulf: flights, private jet and road
From Bangkok, you fly to Koh Samui or drive to Hua Hin. Samui Airport is privately owned and run by Bangkok Airways, and it opens from 06:00 to 22:00. Hua Hin is about 200 kilometres from Bangkok by road, and the Tourism Authority of Thailand describes it as a 2.5-hour drive.
Koh Samui. Fly from Suvarnabhumi or from other Asian hubs. A private jet can land with permission from the Civil Aviation Authority of Thailand, within the airport's opening hours.
Hua Hin. The State Railway of Thailand's Special Express 43 leaves Krung Thep Aphiwat at 07:30 and reaches Hua Hin at 10:31. No airline flies Bangkok to Hua Hin. Hua Hin Airport handles private jets. A private car door to door is the simplest choice.
Koh Phangan and Koh Tao. Neither island has an airport. Fly to Koh Samui and cross by boat, or take the train or fly to Chumphon for Koh Tao.
Plan a Gulf trip with Tanner
Give Tanner your dates and group size. If the Andaman coast suits your month better than the Gulf, we say so. One planner chooses the beach and villa and books the flights, boats and drivers as one trip. Our Thai team is on the island, and one contact handles every detail.
Example plan: four nights in a north-coast Samui villa with a chef, then a yacht day to Ang Thong. Add a speedboat lunch on Koh Phangan's quiet north coast and a last dinner in Bophut's Fisherman's Village. We get back to you right away.
