There's no airport on Koh Chang and no train to it — you travel (or fly) to the Trat mainland, then cross by car ferry in about 30–45 minutes. Compare the bus, the flight to Trat, driving and the ferry itself, with real times and costs.
The first thing to understand before you plan is that Koh Chang is Thailand's second-largest island, out in Trat province on the far eastern coast near the Cambodian border — and there's no airport on the island and no train line to it. Everyone has to reach the Trat mainland first and then take a car ferry across. So the journey always comes in two stages: stage one gets you from Bangkok to the ferry pier (by bus/minivan, by flying to Trat Airport, or by driving), and stage two is the ferry crossing from the Laem Ngop piers onto the island, roughly 30–45 minutes. The thing to plan around is making sure stage one reaches the pier before the last ferry, so you don't get stranded on the mainland overnight.
The main crossing point is in Laem Ngop, Trat. The principal piers are Ao Thammachat and Centre Point, and the boats dock on Koh Chang at Ao Sapparot / Dan Kao. The piers are about 20–30 minutes by road from Trat town.
From Bangkok you can reach the Trat piers three 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.
Koh Chang has no train and no airport on the island — every route is about reaching the pier first and then crossing by ferry. Read this before you book.
When the ferry docks on Koh Chang you still have a short hop to your beach, as the beaches are spread along the west-coast road.
The ferry docks on the island at Ao Sapparot or Dan Kao, up at the northern end — which isn't the resort beaches themselves. The main beaches — White Sand, Klong Prao, Kai Bae and Lonely Beach — run south along the west-coast road, so you'll travel another 10–40 minutes depending on the beach. There are only a few ways to make that final hop; pick the one that matches how you arrived.
Songthaews wait at the ferry pier and run along the west-coast road to the beaches, charging by distance and per person — the further beaches (Lonely Beach, Bang Bao) cost more. Tell the driver your beach or hotel name clearly.
If you bought a combined coach or minivan ticket, many include onward transport on the island that drops you at your beach or hotel, so there's no songthaew to sort. It's the easiest for first-timers — check at purchase which beach it covers.
If you brought a car or motorbike on the ferry, you simply continue to your accommodation — total freedom. Just take care: some stretches are very steep, especially between Kai Bae and Lonely Beach, so ride slowly and check your brakes first.
Koh Chang is a remote island: there's no train, no metro, no public bus network, and Grab is essentially unavailable. Getting around mainly means songthaews and rented cars or scooters, so plan your island transport ahead.
Koh Chang isn't hard to reach, but the classic slip-up is missing the ferry because the road-plus-boat timing was off. Sort these four things before you leave and the whole trip runs far more smoothly.
Plan to reach the pier before the last ferry of the day (usually late afternoon to early evening, and fewer in the low season). If you arrive after the boats stop, you'll have to stay over on the Trat mainland — so always pad out time for the road plus the transfer.
From November to April and on long weekends (Songkran, New Year) minivan, coach and air tickets sell out fast and prices climb. Book ahead, and consider a combined coach-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. If you'll rent a scooter, mind the very steep roads around Kai Bae and Lonely Beach — check the brakes, wear a helmet and ride slowly.
Sort a SIM or eSIM for maps, booking transport and contacting your hotel, and be clear which beach you're staying on — the songthaew fare from the pier varies by distance, so it helps you budget.