There's no airport on Koh Phangan and no train to it — the last leg is always a ferry. You can come via Koh Samui (fastest), via the Surat Thani mainland (cheapest), from Koh Tao, or from Krabi/Phuket. Compare the real times and costs before you set off.
The first thing to understand before you plan is that Koh Phangan is an island in the Gulf of Thailand, in Surat Thani province, sitting between Koh Samui to the south and Koh Tao to the north — and there's no airport on the island and no train line to it. Everyone arrives by ferry on the final leg. So the journey always comes in two stages: stage one gets you to a ferry departure point — and there are several choices: fly into Samui then take a ferry, fly into the Surat Thani mainland then a bus + ferry, take an overnight train or bus from Bangkok to Surat Thani, or continue by ferry from Koh Tao / Krabi / Phuket — and stage two is the ferry crossing onto the island at Thong Sala, the main pier. The thing to plan around is making sure stage one reaches the departure point before the last ferry, so you don't get stranded on one side overnight.
The island's main pier is at Thong Sala, on the southwest coast. It's both the arrival point and a small town hub, with shops, ATMs and songthaews waiting. Some ferry operators (and sailings around the Full Moon Party) use Haad Rin in the south instead, so check which pier your ticket lands at.
From Bangkok you can reach Koh Phangan several main ways, each differing in time, cost and comfort. Pick one, then read the option that matches you — they all finish with the same ferry crossing to Thong Sala.
Koh Phangan has no train and no airport on the island — every route is about reaching a ferry departure point first and then crossing to Thong Sala. Read this before you book.
When the ferry docks at Thong Sala you still have a short hop to your beach, as the beaches are spread around the island and some roads are very steep.
The ferry docks on the island at Thong Sala, on the southwest coast — a small town, not the main resort beaches themselves. The popular beaches — Haad Rin (the Full Moon Party) in the south, Thong Nai Pan in the northeast, and Sri Thanu / Haad Yao in the west — are spread around the island, so you'll travel another 15–60 minutes depending on the beach. There are only a few ways to make that final hop; pick the one that matches how you arrived and where you're staying.
Songthaews wait at Thong Sala pier and run to the beaches, charging by distance and per person — the further beaches on steeper roads (Thong Nai Pan, Haad Rin, Bottle Beach) cost more. Tell the driver your beach or hotel name clearly, and agree the price before you get in.
Many resorts, especially around Thong Nai Pan and the remote beaches, offer a pickup from Thong Sala pier (arrange ahead; some free, some charged). Some ferry tickets include onward transport on the island too. It's the easiest for first-timers — check at booking which beach it covers.
You can rent a scooter at Thong Sala and around the beaches for total freedom, but Koh Phangan's roads are notoriously steep and winding, especially the hills up to Thong Nai Pan, Bottle Beach and Haad Rin, where accidents are common. Rent only if you're an experienced rider, always wear a helmet, and never ride back from the Full Moon Party after drinking.
Koh Phangan is an island: there's no train, no metro, no public bus network, and Grab is essentially unavailable. Getting around mainly means songthaews, rented scooters, and longtail / water taxis to remote beaches like Bottle Beach, so plan your island transport ahead.
Koh Phangan isn't hard to reach, but the classic slip-up is missing the ferry because the flight-or-road-plus-boat timing was off, or hitting a closed sea in the monsoon. Sort these four things before you leave and the whole trip runs far more smoothly.
Plan to reach the departure point before the last ferry of the day, and in the monsoon (Oct–Dec) check the operators' notices on the day you travel, as rough seas can thin out or cancel sailings. If you arrive after the boats stop you'll have to stay over on one side, so always pad out the time.
From February to April, on long weekends, and especially around the monthly Full Moon Party, flights, ferries and rooms sell out fast and prices climb. Book ahead, and consider a combined bus-plus-ferry ticket for better value and less hassle.
The island has no train, metro or public bus, and Grab is essentially unavailable; the beaches are spread out and many roads are very steep. If you'll rent a scooter, mind the hills up to Thong Nai Pan, Bottle Beach and Haad Rin — check the brakes, wear a helmet, ride slowly, and don't ride after drinking.
Sort a SIM or eSIM for maps, booking transport and contacting your hotel (signal can be patchy on remote beaches), and be clear which beach you're staying on — the songthaew fare from the pier varies by distance, so it helps you budget.