Tip · Go midweek. Ao Wong Duean for a first visit, anywhere south of it if you want quiet. On a Saturday, Hat Sai Kaew is Bangkok with sand. On a Tuesday, the same beach is close to empty.
Most people who want a beach from Bangkok make the same mistake: they fly to Phuket or Samui and lose a full day at each end getting there and back. If you've only got three or four days, Koh Samet gets you white sand and clear water for the price of a bus ticket, and you're on the beach by lunchtime.
I went once, during the 2011 floods, when a good chunk of Bangkok was stacking sandbags and we wanted out for a few days. Samet was dry, quiet and three or four hours door to door, and it was a pretty good few days. We stayed down at Ao Kiu at the southern end, if I remember right, which shapes the advice below. That was a while ago, so treat the prices below as this year's rather than my memory, but the reasons for going haven't changed and I'd make the same call today.
Bangkok Thais have been going to Koh Samet for decades and on a long weekend it fills up completely, so nobody should call it undiscovered. Western tourists mostly don't come, because the flights go south and the guidebooks push you the same way. You get an island with a national park and beaches you'd happily photograph, without the Phuket infrastructure or the Phuket prices. For a short trip from the capital, in my opinion, that's the right trade.
Hat Sai Kaew. Photo by Adam, CC BY 2.0.
Why Samet and not somewhere else
Look at the map and the options near Bangkok are Pattaya, Hua Hin, Koh Chang and Koh Samet. Pattaya isn't the beach you're picturing. Hua Hin is a nice town with a mediocre beach, and I like it for other reasons (see the Hua Hin post), but the water is upper Gulf brown. Koh Chang is bigger and greener and, in my opinion, a better island for a week, but it's six or seven hours each way, which is too much of a three-day trip spent in a minivan.
Koh Samet is the one that fits. It's small (about six kilometres top to bottom), it has fine white sand on the east coast, and the water is clear rather than the murky green you get at Bang Saen. It's also a national park, which keeps the building in check.
Koh Samet also gets less rain than any other Thai island I know of. It's a low, small island sitting close to the mainland, and the figures people quote for it are well under what Phuket, Samui or Koh Chang get, where the mountains wring the monsoon out over the coast. In practice that means wet-season rain tends to come as a short afternoon burst rather than a grey week. Our trip was in the tail of the rainy season, with Bangkok under water, and Samet was dry the whole time. If your dates land between May and October and you still want a beach, Samet is the safest bet within reach of Bangkok.
Getting there
The trip is in two parts: Bangkok to Ban Phe pier on the Rayong coast, then a boat.
From Bangkok, go to the Eastern Bus Terminal at Ekkamai, which is right across the road from Ekkamai BTS. Buses and minivans run to Ban Phe through the day, roughly hourly from about 6am until late afternoon. The bus is around 175 THB and takes about three and a half hours with a couple of stops. The minivan is around 250 THB, takes the motorway and doesn't stop, so it's the one I'd take. You can also book a bus and ferry combination online, which is worth doing on a Friday or before a Thai holiday when the minivans fill.
Book transport
Getting to Koh Samet
Minivans and buses leave from Ekkamai. Compare operators and book ahead on 12Go.
At Ban Phe you have two choices. The slow ferry to Na Dan pier on the north of the island costs 50–70 THB, takes about 40 minutes, and runs from early morning until around 6pm. The speedboats cost 200–500 THB per person depending on which beach you want, and drop you straight on the sand at your beach in ten or fifteen minutes. If you're staying south of Ao Wong Duean, the speedboat is worth it, because otherwise you're taking the ferry and then a songthaew across the island anyway.
The pier at Na Dan. Photo by PA, CC BY-SA 4.0.
There's a national park fee at the checkpoint just outside Na Dan village: 200 THB for foreigners, 100 THB for children. It's a one-off that covers you for the week, so keep the ticket. It is not a scam, even though the price difference between Thais and foreigners makes it feel like one.
From Na Dan, songthaews (pickup trucks with benches) run down the east coast to each beach on fixed fares. Hat Sai Kaew is close enough to walk in ten or fifteen minutes if you're not carrying much.
The beaches, north to south
The island is a long wedge with all the beaches on the east coast except one. Roughly, the further south you go, the quieter it gets.
Hat Sai Kaew is the big one at the top: the longest beach, the finest sand, and by a distance the busiest. It's lined with restaurants that put tables and mats on the sand in the evening and run fire shows after dark. On a weekday it's good. On a Saturday it is the beach that Bangkok goes to, and you'll know it.
Ao Hin Khok and Ao Phai are the next two, small and a short walk over the rocks from Sai Kaew. This is where the cheaper guesthouses and the backpacker bars are. Ao Phai is a good compromise if you want to be near the action without sleeping in it.
Ao Wong Duean sits in the middle: a wide crescent bay with its own speedboat pier, a row of mid-range resorts and enough restaurants to eat somewhere different each night. It's my pick for a first visit: enough going on in the evening, quiet at night.
Ao Wong Duean in the early morning. Photo by Eltorodeoro, CC BY-SA 4.0.
South of Wong Duean the island changes gear. Ao Thian (Candlelight Beach) is a string of small coves, Ao Wai is one quiet bay with one resort, and Ao Kiu at the bottom is where we stayed in 2011: a small bay, one resort, decent snorkelling off the rocks and not much else, which was the point. The northern beaches above are partly from walking up the coast on that trip and partly from what I've read since. If the point of the trip is to read a book and swim, and you've already done the busy end once, the south is where I'd go.
Ao Prao is the one beach on the west coast, and it's the expensive one, with three resorts and the island's only sunset. Nice, but you're cut off from everything else and you'll pay for it.
Where to stay
Hotels on Koh Samet are priced for Bangkok weekenders, which means midweek rates are reasonable and Friday and Saturday nights can double. If you can, arrive on a Sunday or Monday and leave before the weekend. You'll get a better room, a quieter beach and a cheaper bill.
I'd book the first night at least, because the speedboat drops you at a specific beach and you don't want to be walking the coast with a bag. You can compare what's on each beach on Agoda. Outside long weekends and the December to January peak, you can usually find a room on arrival, but I wouldn't count on it at Wong Duean or Ao Prao.
Bring cash. There are ATMs at Na Dan, Sai Kaew and Wong Duean, and I wouldn't count on anything south of that. Most of the smaller resorts and every beach restaurant want baht.
When to go
November to February is the best of it, with cool mornings and calm sea. March and April are hot but still dry. From May to October the rain arrives, but as above, Samet gets far less of it than the southern islands, mostly in short afternoon bursts, and it's cheaper and emptier.
The day of the week matters more than the month. Avoid Thai public holidays and long weekends entirely unless you've booked well ahead, because the island sells out. Songkran in April and the New Year period are the worst. A Tuesday to Thursday stay in any month is a different island from a Friday to Sunday one.
What I'd skip
The jet skis and banana boats at Sai Kaew. Jet-ski operators around Thailand have a long record of claiming you damaged the machine and asking for cash on return, and Samet is no exception. The bundled speedboat and island tour sold on the pier at Ban Phe, which is more boat time than beach time. And Hat Sai Kaew itself on a weekend, when the same money gets you a quieter bay twenty minutes south.
I'd also not try to do Samet as a day trip. Seven hours of travel for four hours of beach isn't worth it. Two nights is the minimum that makes sense, three is right, and after four you'll want to move on, because the island is small and you'll have seen it.
For the trip out, sort your ride to Ekkamai with Grab rather than a taxi from the hotel rank. If you're deciding how many places to fit into the whole trip, the trip planning post makes the case for Bangkok plus one region, and a short Samet stop is one of the easier ways to get a beach into a Bangkok-heavy itinerary without adding a flight.
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